diff --git a/app/address/[address]/components/AddressGraph.tsx b/app/address/[address]/components/AddressGraph.tsx
index 7856efe6..d00bd67d 100644
--- a/app/address/[address]/components/AddressGraph.tsx
+++ b/app/address/[address]/components/AddressGraph.tsx
@@ -81,7 +81,7 @@ export function AddressGraph({ address }: { address: string }) {
               <div><dt className="text-muted">Indexed transactions</dt><dd className="mt-1 text-secondary font-mono">{selected.peer.txCount.toLocaleString('en-US')}</dd></div>
             </> : null}
           </dl>
-          <Link href={`/address/${selected.id}`} className="mt-5 inline-flex rounded border border-cipher-border px-3 py-2 text-xs font-mono text-primary hover:bg-cipher-hover">Open address →</Link>
+          <Link href={`/address/${selected.id}`} prefetch={false} className="mt-5 inline-flex rounded border border-cipher-border px-3 py-2 text-xs font-mono text-primary hover:bg-cipher-hover">Open address →</Link>
         </div> : <div><h3 className="text-sm font-semibold text-primary">Inspect a connection</h3><p className="mt-2 text-xs leading-relaxed text-muted">Select a node or choose an address below. Its details stay open while you explore.</p></div>}
         <div className="mt-5 border-t border-cipher-border pt-4">
           <label htmlFor="connection-search" className="text-xs text-muted">Find a displayed address or label</label>
diff --git a/app/address/[address]/components/AddressHeroCard.tsx b/app/address/[address]/components/AddressHeroCard.tsx
index 936cd054..30ec5249 100644
--- a/app/address/[address]/components/AddressHeroCard.tsx
+++ b/app/address/[address]/components/AddressHeroCard.tsx
@@ -36,8 +36,8 @@ export function AddressHeroCard({ data, priceData, crossChain, totalTxCount }: {
         </dl>
       </div>
       {(funding || (crossChain && crossChain.totalSwaps > 0)) && <div className="flex flex-wrap gap-x-8 gap-y-3 border-t border-cipher-border px-5 sm:px-7 py-4 text-xs text-muted">
-        {funding && <p>First funding <Link href={`/tx/${funding.txid}`} className="ml-2 text-secondary underline underline-offset-4 hover:text-primary">{funding.amountZec.toLocaleString('en-US', { maximumFractionDigits: 8 })} {CURRENCY} ↗</Link>
-          {funding.isCoinbase ? ' · Mining reward' : funding.funderAddress ? <> · From <Link className="text-secondary hover:text-primary" href={`/address/${funding.funderAddress}`}>{funding.funderLabel || `${funding.funderAddress.slice(0, 6)}…${funding.funderAddress.slice(-4)}`}</Link></> : null}
+        {funding && <p>First funding <Link href={`/tx/${funding.txid}`} prefetch={false} className="ml-2 text-secondary underline underline-offset-4 hover:text-primary">{funding.amountZec.toLocaleString('en-US', { maximumFractionDigits: 8 })} {CURRENCY} ↗</Link>
+          {funding.isCoinbase ? ' · Mining reward' : funding.funderAddress ? <> · From <Link className="text-secondary hover:text-primary" href={`/address/${funding.funderAddress}`} prefetch={false}>{funding.funderLabel || `${funding.funderAddress.slice(0, 6)}…${funding.funderAddress.slice(-4)}`}</Link></> : null}
         </p>}
         {crossChain && crossChain.totalSwaps > 0 && <p>Bridge records <span className="ml-2 font-mono text-secondary">{crossChain.totalSwaps.toLocaleString('en-US')}</span> · {crossChain.entryCount} in / {crossChain.exitCount} out</p>}
       </div>}
diff --git a/app/address/[address]/components/AddressSummary.tsx b/app/address/[address]/components/AddressSummary.tsx
index a8b1dced..3a48a817 100644
--- a/app/address/[address]/components/AddressSummary.tsx
+++ b/app/address/[address]/components/AddressSummary.tsx
@@ -36,7 +36,7 @@ export function AddressSummary({ data, totalTxCount }: AddressSummaryProps) {
     if (funding.funderLabel && funding.funderAddress) {
       return (
         <Link
-          href={`/address/${funding.funderAddress}`}
+          href={`/address/${funding.funderAddress}`} prefetch={false}
           className="text-cipher-gold hover:text-primary transition-colors"
         >
           {funding.funderLabel}
@@ -46,7 +46,7 @@ export function AddressSummary({ data, totalTxCount }: AddressSummaryProps) {
     if (funding.funderAddress) {
       return (
         <Link
-          href={`/address/${funding.funderAddress}`}
+          href={`/address/${funding.funderAddress}`} prefetch={false}
           className="text-cipher-gold hover:text-primary transition-colors"
         >
           {shortAddr(funding.funderAddress)}
diff --git a/app/address/[address]/components/TransactionTable.tsx b/app/address/[address]/components/TransactionTable.tsx
index 5a5fcb48..0b3b4bb3 100644
--- a/app/address/[address]/components/TransactionTable.tsx
+++ b/app/address/[address]/components/TransactionTable.tsx
@@ -22,7 +22,7 @@ export function TransactionTable({ address, data, currentPage, totalPages, pageS
       if (other === 'shielded') return <TxTypeBadge category="shielded" />;
       return other && other !== address ? <HashLink value={other} href={`/address/${other}`} lead={6} tail={4} copy={false} /> : <span className="text-xs text-muted">—</span>;
     } },
-    { id: 'block', header: 'Block', className: 'hidden md:table-cell', cell: tx => tx.blockHeight ? <Link href={`/block/${tx.blockHeight}`} className="text-xs font-mono text-secondary hover:text-primary">{tx.blockHeight.toLocaleString('en-US')}</Link> : <span className="text-xs text-muted">—</span> },
+    { id: 'block', header: 'Block', className: 'hidden md:table-cell', cell: tx => tx.blockHeight ? <Link href={`/block/${tx.blockHeight}`} prefetch={false} className="text-xs font-mono text-secondary hover:text-primary">{tx.blockHeight.toLocaleString('en-US')}</Link> : <span className="text-xs text-muted">—</span> },
     { id: 'amount', header: `Balance change (${CURRENCY})`, align: 'right', cell: tx => <span className={`text-xs font-mono whitespace-nowrap ${tx.amount === 0 ? 'text-secondary' : tx.type === 'received' ? 'text-cipher-green' : 'text-danger'}`}>{tx.amount === 0 ? '' : tx.type === 'received' ? '+' : '−'}{Math.abs(tx.amount).toLocaleString('en-US', { maximumFractionDigits: 8 })}</span> },
     { id: 'age', header: 'Age', align: 'right', cell: tx => <RelativeTime timestamp={tx.timestamp} className="text-xs text-muted whitespace-nowrap" /> },
   ];
diff --git a/app/address/[address]/components/UnifiedAddressViewer.tsx b/app/address/[address]/components/UnifiedAddressViewer.tsx
index 174c8f11..69d2b5d6 100644
--- a/app/address/[address]/components/UnifiedAddressViewer.tsx
+++ b/app/address/[address]/components/UnifiedAddressViewer.tsx
@@ -23,7 +23,7 @@ export function UnifiedAddressViewer({ uaComponents, uaLoading, copiedText, onCo
         <div><TxTypeBadge category={receiver.key} /></div>
         <div className="min-w-0">
           {receiver.address ? <div className="flex items-start gap-2"><code className="min-w-0 break-all text-xs text-secondary">{receiver.address}</code><CopyButton text={receiver.address} label={receiver.key} copiedText={copiedText} onCopy={onCopy} /></div> : <p className="text-sm text-secondary">Receiver present · use the Unified Address</p>}
-          {receiver.key === 'transparent' && receiver.address ? <Link className="inline-flex mt-3 rounded border border-cipher-border px-3 py-2 text-xs font-mono text-primary hover:bg-cipher-hover" href={`/address/${receiver.address}`}>View transparent activity →</Link> : <p className="text-xs text-muted mt-2">Balance and history remain private.</p>}
+          {receiver.key === 'transparent' && receiver.address ? <Link className="inline-flex mt-3 rounded border border-cipher-border px-3 py-2 text-xs font-mono text-primary hover:bg-cipher-hover" href={`/address/${receiver.address}`} prefetch={false}>View transparent activity →</Link> : <p className="text-xs text-muted mt-2">Balance and history remain private.</p>}
         </div>
       </div>)}
       {!receivers.length && <p className="p-5 text-sm text-muted">No supported receiver details were returned by the decoder.</p>}
diff --git a/app/api/governance/announcement/route.ts b/app/api/governance/announcement/route.ts
index 59b41aac..e408eca8 100644
--- a/app/api/governance/announcement/route.ts
+++ b/app/api/governance/announcement/route.ts
@@ -1,11 +1,13 @@
 import { getGovernanceCatalog } from '@/lib/governance-data';
-import { selectAnnouncement } from '@/lib/governance';
+import { announcementCacheHeaders, buildAnnouncementSnapshot } from '@/lib/governance-announcement';
 import { getNetwork } from '@/lib/seo';
 
 export async function GET() {
-  if (getNetwork() !== 'mainnet') return Response.json({ announcement: null }, { headers: { 'X-Robots-Tag': 'noindex' } });
+  if (getNetwork() !== 'mainnet') return Response.json(
+    { announcement: null, generatedAt: Date.now(), nextChangeAt: null },
+    { headers: announcementCacheHeaders(60) },
+  );
   const catalog = await getGovernanceCatalog();
-  return Response.json({ announcement: selectAnnouncement(catalog, Date.now()) }, { headers: {
-    'Cache-Control': 'no-store', 'X-Robots-Tag': 'noindex',
-  } });
+  const { snapshot, ttl } = buildAnnouncementSnapshot(catalog, Date.now());
+  return Response.json(snapshot, { headers: announcementCacheHeaders(ttl) });
 }
diff --git a/app/block/[height]/FutureBlockView.tsx b/app/block/[height]/FutureBlockView.tsx
index d2edb10e..c5c6219a 100644
--- a/app/block/[height]/FutureBlockView.tsx
+++ b/app/block/[height]/FutureBlockView.tsx
@@ -48,7 +48,7 @@ export function FutureBlockView({
             )}
             <div className="flex flex-wrap items-center justify-center gap-3">
               <Link
-                href={`/block/${targetHeight}`}
+                href={`/block/${targetHeight}`} prefetch={false}
                 className="btn btn-md btn-primary"
               >
                 View Block →
@@ -134,7 +134,7 @@ export function FutureBlockView({
           <dl className="mt-6 grid grid-cols-1 gap-5 border-t border-cipher-border pt-6 sm:grid-cols-2 sm:gap-8">
             <div>
               <dt className="text-sm text-secondary mb-2">Latest block</dt>
-              <dd className="font-mono text-primary tabular-nums"><Link href={`/block/${currentHeight}`} className="hover:text-cipher-gold transition-colors">#{currentHeight.toLocaleString('en-US')}</Link></dd>
+              <dd className="font-mono text-primary tabular-nums"><Link href={`/block/${currentHeight}`} prefetch={false} className="hover:text-cipher-gold transition-colors">#{currentHeight.toLocaleString('en-US')}</Link></dd>
             </div>
             <div>
               <dt className="text-sm text-secondary mb-2">{upgrade ? 'Activation block' : 'Upcoming block'}</dt>
diff --git a/app/block/[height]/components/BlockPageHeader.tsx b/app/block/[height]/components/BlockPageHeader.tsx
index 26c9df76..39915823 100644
--- a/app/block/[height]/components/BlockPageHeader.tsx
+++ b/app/block/[height]/components/BlockPageHeader.tsx
@@ -16,7 +16,7 @@ function BlockNavPill({ height, hash, direction }: { height: number; hash?: stri
   const disabled = !hash;
   return (
     <Link
-      href={disabled ? '#' : `/block/${height}`}
+      href={disabled ? '#' : `/block/${height}`} prefetch={false}
       aria-disabled={disabled}
       className={`inline-flex items-center gap-1.5 px-3 py-1.5 rounded-md border text-xs font-mono transition-colors ${
         disabled
diff --git a/app/block/[height]/components/BlockPageSkeleton.tsx b/app/block/[height]/components/BlockPageSkeleton.tsx
index 5f3175a4..4c8dc02a 100644
--- a/app/block/[height]/components/BlockPageSkeleton.tsx
+++ b/app/block/[height]/components/BlockPageSkeleton.tsx
@@ -1,3 +1,4 @@
+import Link from 'next/link';
 import { SkeletonTable } from '@/components/ui/EmptyState';
 import { Skeleton } from '@/components/ui/Skeleton';
 import { Card, CardHeader, CardBody } from '@/components/ui/Card';
@@ -50,6 +51,14 @@ export function BlockPageSkeleton({
             </>
           )}
         </p>
+        {initialSummary?.isOrphaned && initialSummary.canonicalReplacementHeight != null && (
+          <p className="mt-2 text-xs sm:text-sm text-secondary">
+            Canonical replacement at this height:{' '}
+            <Link href={`/block/${initialSummary.canonicalReplacementHeight}`} prefetch={false} className="text-brand-gold hover:underline">
+              Zcash block #{initialSummary.canonicalReplacementHeight.toLocaleString('en-US')}
+            </Link>.
+          </p>
+        )}
         {/* Server-seeded facts from the SEO resolution fetch — real content
             instead of a shimmer while the full block detail loads client-side. */}
         {initialSummary && (initialSummary.timestamp != null || initialSummary.transactionCount != null || initialSummary.size != null) && (
diff --git a/app/block/[height]/components/types.ts b/app/block/[height]/components/types.ts
index 999ee45f..5a18e9a7 100644
--- a/app/block/[height]/components/types.ts
+++ b/app/block/[height]/components/types.ts
@@ -60,6 +60,8 @@ export interface BlockPageSummary {
   hash: string;
   firstSeenAt?: string | null;
   isOrphaned: boolean;
+  /** Present only when the API identifies a different canonical block at this height. */
+  canonicalReplacementHeight?: number | null;
   /**
    * Extra fields already available from the server-side block resolution
    * (`getBlockResolution` in lib/seo.ts) used for SEO metadata. Threading
diff --git a/app/block/[height]/page.tsx b/app/block/[height]/page.tsx
index 6c75cffc..56cdbab2 100644
--- a/app/block/[height]/page.tsx
+++ b/app/block/[height]/page.tsx
@@ -5,6 +5,7 @@ import {
   getApiUrl,
   getNetwork,
   getBlockResolution,
+  BLOCK_HASH_PATTERN,
   normalizeBlockIdentifier,
   type BlockRecord,
 } from '@/lib/seo';
@@ -92,6 +93,10 @@ export default async function BlockPage({
   const height = Number(block.height);
   const hash = block.hash.toLowerCase();
   const isOrphaned = block.isOrphaned === true;
+  const replacementHash = block.canonicalBlock?.hash;
+  const canonicalReplacementHeight = isOrphaned && typeof replacementHash === 'string'
+    && BLOCK_HASH_PATTERN.test(replacementHash) && replacementHash.toLowerCase() !== hash
+    ? height : null;
   const rawTransactionCount = block.transactionCount ?? block.transaction_count ?? null;
   const transactionCount = rawTransactionCount === null || rawTransactionCount === undefined
     ? null
@@ -104,6 +109,7 @@ export default async function BlockPage({
     height,
     hash,
     isOrphaned,
+    canonicalReplacementHeight,
     timestamp: Number.isFinite(timestamp) ? timestamp : null,
     transactionCount: Number.isFinite(transactionCount) ? transactionCount : null,
     size: Number.isFinite(size) ? size : null,
diff --git a/app/blocks/BlocksClient.tsx b/app/blocks/BlocksClient.tsx
index 86be0966..67ff549e 100644
--- a/app/blocks/BlocksClient.tsx
+++ b/app/blocks/BlocksClient.tsx
@@ -112,7 +112,7 @@ function blockColumns(blocks: Block[], trailingBlock: Block | null, schedule: Bl
       skeletonWidth: 'w-24',
       cell: (block) => (
         <div className="flex items-center gap-2">
-          <Link href={`/block/${block.height}`} className="font-mono text-sm text-primary hover:text-primary transition-colors">
+          <Link href={`/block/${block.height}`} prefetch={false} className="font-mono text-sm text-primary hover:text-primary transition-colors">
             {block.height.toLocaleString()}
           </Link>
           {block.finality_status === 'Finalized' && (
diff --git a/app/finalizer/[pubkey]/page.tsx b/app/finalizer/[pubkey]/page.tsx
index 07a72407..4dd04657 100644
--- a/app/finalizer/[pubkey]/page.tsx
+++ b/app/finalizer/[pubkey]/page.tsx
@@ -384,7 +384,7 @@ export default function FinalizerPage() {
                         <StakingActionBadge type={a.action_type} compact />
                       </td>
                       <td className="px-3 sm:px-4 py-3">
-                        <Link href={`/block/${a.block_height}`} className="text-cipher-gold hover:underline font-mono">
+                        <Link href={`/block/${a.block_height}`} prefetch={false} className="text-cipher-gold hover:underline font-mono">
                           #{a.block_height.toLocaleString()}
                         </Link>
                       </td>
@@ -609,6 +609,7 @@ function DelegatorsPanel({ actions }: { actions: StakeAction[] }) {
                     <td className="px-3 sm:px-4 py-3">
                       <Link
                         href={`/block/${d.lastActionHeight}`}
+                        prefetch={false}
                         className="text-cipher-gold hover:underline font-mono"
                       >
                         #{d.lastActionHeight.toLocaleString()}
diff --git a/app/governance/HowToVote.tsx b/app/governance/HowToVote.tsx
index 4020603b..42fc95ea 100644
--- a/app/governance/HowToVote.tsx
+++ b/app/governance/HowToVote.tsx
@@ -27,7 +27,7 @@ export function HowToVote({ snapshotHeight }: { snapshotHeight?: number }) {
           <h3 className="text-sm font-medium text-primary"><span className="mr-2 font-mono text-cipher-gold">02</span>Check your eligible balance</h3>
           <p className="mt-2 text-sm leading-relaxed text-secondary">Follow the wallet’s eligibility check. Each poll uses a snapshot: an earlier point in the blockchain used to determine which funds can vote.</p>
           {snapshotHeight !== undefined && (
-            <Link href={`/block/${snapshotHeight}`} className="mt-2 inline-block text-xs text-cipher-gold hover:underline">
+            <Link href={`/block/${snapshotHeight}`} prefetch={false} className="mt-2 inline-block text-xs text-cipher-gold hover:underline">
               This poll’s snapshot: block {snapshotHeight.toLocaleString('en-US')} →
             </Link>
           )}
diff --git a/app/governance/nu7/NU7VoteClient.tsx b/app/governance/nu7/NU7VoteClient.tsx
index bbf09587..2ebcb935 100644
--- a/app/governance/nu7/NU7VoteClient.tsx
+++ b/app/governance/nu7/NU7VoteClient.tsx
@@ -275,7 +275,7 @@ export function NU7VoteClient({ initialData, resultsState, resultsContent, initi
             {countdownLabel}
           </span>
           {phase === 'pre-snapshot' && (
-            <Link href={`/block/${NU7_VOTE.snapshotHeight}`} className="text-caption font-mono text-muted hover:text-primary transition-colors ml-auto">
+            <Link href={`/block/${NU7_VOTE.snapshotHeight}`} prefetch={false} className="text-caption font-mono text-muted hover:text-primary transition-colors ml-auto">
               Block #{NU7_VOTE.snapshotHeight.toLocaleString()}
             </Link>
           )}
diff --git a/app/name/[name]/NameClient.tsx b/app/name/[name]/NameClient.tsx
index 0b65f5c0..b6f90841 100644
--- a/app/name/[name]/NameClient.tsx
+++ b/app/name/[name]/NameClient.tsx
@@ -106,7 +106,7 @@ function RegisteredView({
           <Field label="Resolves to">
             <div className="flex items-center">
               <Link
-                href={`/address/${registration.address}`}
+                href={`/address/${registration.address}`} prefetch={false}
                 className="font-mono text-sm hover:text-primary transition-colors break-all"
               >
                 {registration.address}
@@ -128,7 +128,7 @@ function RegisteredView({
           <Field label="Block">
             <div className="flex items-center">
               <Link
-                href={`/block/${registration.height}`}
+                href={`/block/${registration.height}`} prefetch={false}
                 className="font-mono text-sm hover:text-primary transition-colors"
               >
                 {registration.height.toLocaleString('en-US')}
@@ -191,7 +191,7 @@ function RegisteredView({
                       </td>
                       <td className="py-2 pr-4 font-mono">
                         <Link
-                          href={`/block/${e.height}`}
+                          href={`/block/${e.height}`} prefetch={false}
                           className="hover:text-primary transition-colors"
                         >
                           {e.height.toLocaleString('en-US')}
diff --git a/app/network/NetworkClient.tsx b/app/network/NetworkClient.tsx
index 36bf9087..5250be16 100644
--- a/app/network/NetworkClient.tsx
+++ b/app/network/NetworkClient.tsx
@@ -156,7 +156,7 @@ export default function NetworkClient({ initialData }: { initialData: NetworkPag
           </dl>
           <dl id="network-overview" className="network-section network-summary-grid network-live-facts" aria-label="Current chain activity">
             {[
-              { label: 'Latest block', value: height != null ? <Link href={`/block/${height}`} className="hover:text-cipher-gold">{height.toLocaleString()}</Link> : '—', hint: stats ? `Block timestamp · ${blockAgeLabel(stats.blockchain.latestBlockTime, now)}` : 'Awaiting chain data' },
+              { label: 'Latest block', value: height != null ? <Link href={`/block/${height}`} prefetch={false} className="hover:text-cipher-gold">{height.toLocaleString()}</Link> : '—', hint: stats ? `Block timestamp · ${blockAgeLabel(stats.blockchain.latestBlockTime, now)}` : 'Awaiting chain data' },
               { label: 'Average block interval', value: stats?.mining.avgBlockTime != null ? `${stats.mining.avgBlockTime.toFixed(1)}s` : '—', hint: stats?.mining.targetBlockTime != null ? `Observed · protocol target ${stats.mining.targetBlockTime}s` : 'Observed · protocol target unavailable' },
               { label: 'Transactions · 24h', value: txCount?.toLocaleString() ?? '—', hint: stats?.blockchain.tx24hExclCoinbase != null ? 'Confirmed · coinbase excluded' : 'Confirmed · includes coinbase' },
               { label: 'Estimated hashrate · 24h', value: stats?.mining.hashrateEstimate ? stats.mining.networkHashrate : '—', hint: <Link href="/mining#metrics" className="hover:text-primary underline underline-offset-4">Trailing 24-hour estimate →</Link> },
diff --git a/app/network/page.tsx b/app/network/page.tsx
index 9d00e9c4..0c072e88 100644
--- a/app/network/page.tsx
+++ b/app/network/page.tsx
@@ -70,7 +70,7 @@ export default async function NetworkPage() {
     <section className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 pb-12">
       <div className="border-t border-cipher-border pt-6 max-w-3xl text-sm text-muted space-y-2">
         <h2 className="font-mono font-medium text-secondary">About these observations</h2>
-        {nu7Height != null && <p>The serving node announces NU7 at <Link href={`/block/${nu7Height}`} className="text-brand-gold hover:underline">block #{nu7Height.toLocaleString('en-US')}</Link> on Zcash {network}. {nu7Active ? <>The upgrade is active; explore <Link href="#nu7-accounting" className="text-brand-gold hover:underline">fee allocation and NSM accounting</Link> below.</> : <>View its canonical block or the estimated activation countdown.</>}</p>}
+        {nu7Height != null && <p>The serving node announces NU7 at <Link href={`/block/${nu7Height}`} prefetch={false} className="text-brand-gold hover:underline">block #{nu7Height.toLocaleString('en-US')}</Link> on Zcash {network}. {nu7Active ? <>The upgrade is active; explore <Link href="#nu7-accounting" className="text-brand-gold hover:underline">fee allocation and NSM accounting</Link> below.</> : <>View its canonical block or the estimated activation countdown.</>}</p>}
         <p>Chain statistics, recent blocks and node discovery are separate observations and can update at different times. Block cadence uses timestamps recorded in blocks; these are not measurements of when this explorer received them.</p>
         <p>The map shows observed reachable nodes, not a census of every Zcash node. Peer connections and disk usage in Technical details describe this explorer’s node. Observed transaction fees describe past transactions and are not fee recommendations.</p>
       </div>
diff --git a/app/reorgs/page.tsx b/app/reorgs/page.tsx
index 2cec2072..e76b8e3a 100644
--- a/app/reorgs/page.tsx
+++ b/app/reorgs/page.tsx
@@ -100,7 +100,7 @@ const forkColumns: DataTableColumn<ForkEvent>[] = [
     id: 'height',
     header: 'Height',
     cell: (fork) => (
-      <Link href={`/block/${fork.forkHeight}`} className="text-cipher-gold hover:underline font-mono text-xs">
+      <Link href={`/block/${fork.forkHeight}`} prefetch={false} className="text-cipher-gold hover:underline font-mono text-xs">
         #{fork.forkHeight.toLocaleString()}
       </Link>
     ),
@@ -381,7 +381,7 @@ export default function UnclesPage() {
           <div>
             <span className="text-caption text-muted font-mono uppercase">Hash</span>
             <Link
-              href={isOrphan ? `/block/${block.hash}` : `/block/${height}`}
+              href={isOrphan ? `/block/${block.hash}` : `/block/${height}`} prefetch={false}
               className={`text-xs font-mono break-all hover:underline block mt-0.5 ${isOrphan ? 'text-cipher-orange' : 'text-cipher-green'}`}
             >
               {block.hash}
@@ -549,7 +549,7 @@ export default function UnclesPage() {
                       onClick={() => setExpandedOrphan(expandedOrphan === block.id ? null : block.id)}
                     >
                       <td className="px-4 h-[44px] border-b border-cipher-border">
-                        <Link href={`/block/${block.height}`} className="text-cipher-gold hover:underline font-mono text-xs" onClick={e => e.stopPropagation()}>
+                        <Link href={`/block/${block.height}`} prefetch={false} className="text-cipher-gold hover:underline font-mono text-xs" onClick={e => e.stopPropagation()}>
                           #{block.height.toLocaleString()}
                         </Link>
                       </td>
@@ -585,7 +585,7 @@ export default function UnclesPage() {
                             <span className="text-xs text-muted">—</span>
                           )
                         ) : block.minerAddress ? (
-                          <Link href={`/address/${block.minerAddress}`} className="text-xs font-mono text-cipher-gold hover:underline truncate block max-w-[120px]" title={block.minerAddress} onClick={e => e.stopPropagation()}>
+                          <Link href={`/address/${block.minerAddress}`} prefetch={false} className="text-xs font-mono text-cipher-gold hover:underline truncate block max-w-[120px]" title={block.minerAddress} onClick={e => e.stopPropagation()}>
                             {block.minerPool}
                           </Link>
                         ) : (
diff --git a/app/tools/anchor-search/AnchorSearchClient.tsx b/app/tools/anchor-search/AnchorSearchClient.tsx
index d307fd16..06d5f4bc 100644
--- a/app/tools/anchor-search/AnchorSearchClient.tsx
+++ b/app/tools/anchor-search/AnchorSearchClient.tsx
@@ -129,7 +129,7 @@ export default function AnchorSearchClient() {
               <div className="space-y-2">
                 {result.canonical.map((block) => (
                   <div key={block.hash} className="p-3 bg-cipher-surface border border-cipher-border rounded-lg flex flex-col sm:flex-row sm:items-center gap-2 sm:gap-4">
-                    <Link href={`/block/${block.height}`} className="text-cipher-gold hover:underline font-mono text-sm">
+                    <Link href={`/block/${block.height}`} prefetch={false} className="text-cipher-gold hover:underline font-mono text-sm">
                       #{block.height.toLocaleString()}
                     </Link>
                     <span className={`text-xs px-2 py-0.5 rounded font-mono ${
diff --git a/app/tools/broadcast/BroadcastClient.tsx b/app/tools/broadcast/BroadcastClient.tsx
index dec7c1ef..0a36c867 100644
--- a/app/tools/broadcast/BroadcastClient.tsx
+++ b/app/tools/broadcast/BroadcastClient.tsx
@@ -264,7 +264,7 @@ export default function BroadcastClient() {
                   View in Mempool
                 </Link>
                 <Link
-                  href={`/tx/${result.txid}`}
+                  href={`/tx/${result.txid}`} prefetch={false}
                   className="btn btn-secondary px-6 text-sm inline-flex items-center gap-2 h-11"
                 >
                   <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
diff --git a/app/tools/decode/DecodeClient.tsx b/app/tools/decode/DecodeClient.tsx
index 2f120381..271e3d37 100644
--- a/app/tools/decode/DecodeClient.tsx
+++ b/app/tools/decode/DecodeClient.tsx
@@ -533,7 +533,7 @@ export default function DecodeClient() {
                                 Previous TX
                               </label>
                               <div className="block-hash-bg px-3 py-2 rounded border border-cipher-border">
-                                <Link href={`/tx/${vin.txid}`}>
+                                <Link href={`/tx/${vin.txid}`} prefetch={false}>
                                   <code className="text-xs text-cipher-gold hover:underline break-all block">
                                     {vin.txid}
                                   </code>
@@ -645,7 +645,7 @@ export default function DecodeClient() {
                               To
                             </label>
                             <div className="block-hash-bg px-3 py-2 rounded border border-cipher-border">
-                              <Link href={`/address/${vout.scriptPubKey.address}`}>
+                              <Link href={`/address/${vout.scriptPubKey.address}`} prefetch={false}>
                                 <code className="text-xs text-cipher-gold hover:underline break-all block">
                                   {vout.scriptPubKey.address}
                                 </code>
diff --git a/app/tx/[txid]/components/FlowChain.tsx b/app/tx/[txid]/components/FlowChain.tsx
index 9e20ef7a..bc24fdba 100644
--- a/app/tx/[txid]/components/FlowChain.tsx
+++ b/app/tx/[txid]/components/FlowChain.tsx
@@ -44,7 +44,7 @@ function FlowAddressNode({ address }: { address: string }) {
   const labelInfo = useAddressLabel(address);
   if (!labelInfo) return <AddressDisplay address={address} className="text-xs" />;
   return (
-    <Link href={`/address/${address}`} className="transition-colors">
+    <Link href={`/address/${address}`} prefetch={false} className="transition-colors">
       <Badge
         color={labelInfo.isOfficial ? 'gold' : 'muted'}
         variant="subtle"
diff --git a/app/tx/[txid]/components/InputsSection.tsx b/app/tx/[txid]/components/InputsSection.tsx
index 3d044a85..711965c3 100644
--- a/app/tx/[txid]/components/InputsSection.tsx
+++ b/app/tx/[txid]/components/InputsSection.tsx
@@ -74,7 +74,7 @@ export function InputsSection({ data, copiedText, onCopy }: InputsSectionProps)
                   </div>
                 ) : input.address ? (
                   <div className="flex items-center gap-1 min-w-0">
-                    <Link href={`/address/${input.address}`} className="min-w-0 block overflow-hidden">
+                    <Link href={`/address/${input.address}`} prefetch={false} className="min-w-0 block overflow-hidden">
                       <code className="text-caption text-primary hover:underline transition-colors font-mono truncate block">
                         {input.address}
                       </code>
diff --git a/app/tx/[txid]/components/MempoolPendingView.tsx b/app/tx/[txid]/components/MempoolPendingView.tsx
index 4b34c379..d0492c92 100644
--- a/app/tx/[txid]/components/MempoolPendingView.tsx
+++ b/app/tx/[txid]/components/MempoolPendingView.tsx
@@ -202,7 +202,7 @@ export function MempoolPendingView({
                       className="flex items-center justify-between py-2 px-3 rounded-lg bg-glass-2"
                     >
                       <Link
-                        href={`/address/${out.address}`}
+                        href={`/address/${out.address}`} prefetch={false}
                         className="text-xs font-mono text-cipher-gold hover:underline truncate max-w-[60%]"
                       >
                         {out.address}
diff --git a/app/tx/[txid]/components/OutputsSection.tsx b/app/tx/[txid]/components/OutputsSection.tsx
index 804f52c9..db5234c8 100644
--- a/app/tx/[txid]/components/OutputsSection.tsx
+++ b/app/tx/[txid]/components/OutputsSection.tsx
@@ -89,7 +89,7 @@ export function OutputsSection({
                 <div className="min-w-0 flex-1 overflow-hidden">
                   {outputAddr ? (
                     <div className="flex items-center gap-1 min-w-0">
-                      <Link href={`/address/${outputAddr}`} className="min-w-0 block overflow-hidden">
+                      <Link href={`/address/${outputAddr}`} prefetch={false} className="min-w-0 block overflow-hidden">
                         <code className="text-caption text-primary hover:underline transition-colors font-mono truncate block">
                           {outputAddr}
                         </code>
diff --git a/app/tx/[txid]/components/TxHeroCard.tsx b/app/tx/[txid]/components/TxHeroCard.tsx
index 3eb740cf..136bbe4b 100644
--- a/app/tx/[txid]/components/TxHeroCard.tsx
+++ b/app/tx/[txid]/components/TxHeroCard.tsx
@@ -76,7 +76,7 @@ export function TxHeroCard({ data, classification, priceUsd }: TxHeroCardProps)
                   {' '}
                   Included in canonical Zcash block{' '}
                   <Link
-                    href={`/block/${data.blockHeight}`}
+                    href={`/block/${data.blockHeight}`} prefetch={false}
                     className="text-primary hover:underline"
                   >
                     #{data.blockHeight.toLocaleString()}
diff --git a/app/tx/[txid]/components/TxOverview.tsx b/app/tx/[txid]/components/TxOverview.tsx
index f9126408..6d51ff57 100644
--- a/app/tx/[txid]/components/TxOverview.tsx
+++ b/app/tx/[txid]/components/TxOverview.tsx
@@ -80,7 +80,7 @@ export function TxOverview({ data }: TxOverviewProps) {
           <div className="flex flex-wrap items-start gap-3">
             <FactBox hug label="Block" tooltip="The block that includes this transaction">
               <div className="flex items-center gap-2 flex-wrap text-sm">
-                <Link href={`/block/${data.blockHeight}`} className="text-primary hover:underline font-mono">
+                <Link href={`/block/${data.blockHeight}`} prefetch={false} className="text-primary hover:underline font-mono">
                   #{data.blockHeight.toLocaleString()}
                 </Link>
                 <span className="text-muted text-xs whitespace-nowrap">
diff --git a/app/txs/TxsClient.tsx b/app/txs/TxsClient.tsx
index 7eb6e2e2..ea65c097 100644
--- a/app/txs/TxsClient.tsx
+++ b/app/txs/TxsClient.tsx
@@ -161,7 +161,7 @@ const txColumns: DataTableColumn<Transaction>[] = [
     align: 'right',
     className: 'hidden sm:table-cell',
     cell: (tx) => (
-      <Link href={`/block/${tx.block_height}`} className="font-mono text-xs text-muted hover:text-primary transition-colors">
+      <Link href={`/block/${tx.block_height}`} prefetch={false} className="font-mono text-xs text-muted hover:text-primary transition-colors">
         #{tx.block_height.toLocaleString()}
       </Link>
     ),
@@ -228,7 +228,7 @@ const shieldedColumns: DataTableColumn<ShieldedFlow>[] = [
     align: 'right',
     className: 'hidden sm:table-cell',
     cell: (flow) => (
-      <Link href={`/block/${flow.blockHeight}`} className="font-mono text-xs text-muted hover:text-primary transition-colors">
+      <Link href={`/block/${flow.blockHeight}`} prefetch={false} className="font-mono text-xs text-muted hover:text-primary transition-colors">
         #{flow.blockHeight.toLocaleString()}
       </Link>
     ),
diff --git a/components/AddressWithLabel.tsx b/components/AddressWithLabel.tsx
index 7d24e8cc..5bcf47fd 100644
--- a/components/AddressWithLabel.tsx
+++ b/components/AddressWithLabel.tsx
@@ -77,7 +77,7 @@ export function AddressWithLabel({
   if (linkable) {
     return (
       <Link
-        href={`/address/${address}`}
+        href={`/address/${address}`} prefetch={false}
         className="hover:text-primary transition-colors"
       >
         {content}
@@ -104,7 +104,7 @@ export function AddressDisplay({
 
   return (
     <Link
-      href={`/address/${address}`}
+      href={`/address/${address}`} prefetch={false}
       // The address is the identifying fact here (this is the hero flow
       // diagram's node in most call sites), so it rests at text-primary
       // like the block hash / reward addresses elsewhere — hover:underline
diff --git a/components/BatchPatternCard.tsx b/components/BatchPatternCard.tsx
index 1fdab97d..e5201357 100644
--- a/components/BatchPatternCard.tsx
+++ b/components/BatchPatternCard.tsx
@@ -132,7 +132,7 @@ export function BatchPatternCard({ pattern }: { pattern: BatchPattern }) {
     {showGraph && <div id={`${cardId}-graph`} className="mt-5 space-y-3"><PrivacyLinkGraph nodes={clusterPanel.graphNodes} edges={clusterPanel.graphEdges} focusNodeId={`cluster:${pattern.clusterHash || pattern.txids[0]}`} height={320} /><p className="text-xs text-muted">The graph summarizes the batch and up to three returned recipient addresses. Grouping does not establish common ownership.</p></div>}
     {expanded && <div id={`${cardId}-members`} className="mt-5">
       <p className="text-xs text-muted mb-3">{memberCount} transaction IDs supplied for {pattern.batchCount} withdrawals. Times are shown in your local timezone.</p>
-      <div className="overflow-x-auto rounded-lg border border-cipher-border"><table className="w-full text-left text-xs"><thead className="bg-cipher-bg text-muted"><tr><th className="p-3 font-medium">Transaction</th><th className="p-3 font-medium">Block</th><th className="p-3 font-medium text-right">Observed</th></tr></thead><tbody className="divide-y divide-cipher-border">{pattern.txids.slice(memberPage * 10, (memberPage + 1) * 10).map((txid, index) => { const row = memberPage * 10 + index; return <tr key={txid} className="hover:bg-cipher-hover"><td className="p-3"><HashLink value={txid} href={`/tx/${txid}`} copy={false} /></td><td className="p-3 font-mono text-secondary">{pattern.heights[row] ? <Link className="hover:underline" href={`/block/${pattern.heights[row]}`}>{pattern.heights[row].toLocaleString()}</Link> : '—'}</td><td className="p-3 text-right whitespace-nowrap text-muted">{pattern.times[row] ? formatTime(pattern.times[row]) : 'Unavailable'}</td></tr>; })}</tbody></table></div>
+      <div className="overflow-x-auto rounded-lg border border-cipher-border"><table className="w-full text-left text-xs"><thead className="bg-cipher-bg text-muted"><tr><th className="p-3 font-medium">Transaction</th><th className="p-3 font-medium">Block</th><th className="p-3 font-medium text-right">Observed</th></tr></thead><tbody className="divide-y divide-cipher-border">{pattern.txids.slice(memberPage * 10, (memberPage + 1) * 10).map((txid, index) => { const row = memberPage * 10 + index; return <tr key={txid} className="hover:bg-cipher-hover"><td className="p-3"><HashLink value={txid} href={`/tx/${txid}`} copy={false} /></td><td className="p-3 font-mono text-secondary">{pattern.heights[row] ? <Link className="hover:underline" href={`/block/${pattern.heights[row]}`} prefetch={false}>{pattern.heights[row].toLocaleString()}</Link> : '—'}</td><td className="p-3 text-right whitespace-nowrap text-muted">{pattern.times[row] ? formatTime(pattern.times[row]) : 'Unavailable'}</td></tr>; })}</tbody></table></div>
       {memberCount > 10 && <div className="flex items-center justify-end gap-3 mt-3 text-xs text-muted"><button className={riskButtonClass} disabled={memberPage === 0} onClick={() => setMemberPage(page => page - 1)}>Previous members</button><span>{memberPage + 1} / {Math.ceil(memberCount / 10)}</span><button className={riskButtonClass} disabled={(memberPage + 1) * 10 >= memberCount} onClick={() => setMemberPage(page => page + 1)}>Next members</button></div>}
     </div>}
   </article>;
diff --git a/components/BlockActivityChart.tsx b/components/BlockActivityChart.tsx
index 1202d268..4ada0bc8 100644
--- a/components/BlockActivityChart.tsx
+++ b/components/BlockActivityChart.tsx
@@ -184,7 +184,7 @@ export function BlockActivityChart({
             <div className="mt-4 h-16 flex items-center justify-center">
               {hoveredBlock ? (
                 <Link
-                  href={`/block/${hoveredBlock.height}`}
+                  href={`/block/${hoveredBlock.height}`} prefetch={false}
                   className="card px-4 py-2.5 flex items-center gap-4 hover:border-cipher-gold transition-colors"
                 >
                   <div>
@@ -283,7 +283,7 @@ function BlockBar({
 
   return (
     <Link
-      href={`/block/${block.height}`}
+      href={`/block/${block.height}`} prefetch={false}
       className={`relative shrink-0 w-[6px] sm:w-[8px] rounded-t-sm border-t ${color} transition-[height,transform,box-shadow] ${
         isHovered ? 'ring-1 ring-cipher-gold' : ''
       } ${isVoting ? 'animate-pulse' : ''}`}
diff --git a/components/CrosslinkChainGraph.tsx b/components/CrosslinkChainGraph.tsx
index 823edc11..0d7fb583 100644
--- a/components/CrosslinkChainGraph.tsx
+++ b/components/CrosslinkChainGraph.tsx
@@ -164,7 +164,7 @@ function PowBlockNode({ data }: NodeProps<Node<PowNodeData>>) {
       />
 
       <Link
-        href={`/block/${block.height}`}
+        href={`/block/${block.height}`} prefetch={false}
         className={`group absolute inset-0 flex items-stretch rounded-lg border ${borderClass} bg-white dark:bg-white/[0.03] overflow-hidden hover:border-cipher-gold/60 hover:shadow-[0_0_20px_rgba(248,188,33,0.12)] transition`}
       >
         <span className={`block w-1 shrink-0 ${accentClass}`} />
diff --git a/components/CrosslinkChainView.tsx b/components/CrosslinkChainView.tsx
index 6071e198..dec32499 100644
--- a/components/CrosslinkChainView.tsx
+++ b/components/CrosslinkChainView.tsx
@@ -293,7 +293,7 @@ function ChainRow({
 
   return (
     <Link
-      href={`/block/${block.height}`}
+      href={`/block/${block.height}`} prefetch={false}
       className={`group flex items-stretch rounded-md border ${borderClass} bg-white dark:bg-white/[0.03] overflow-hidden hover:border-cipher-gold/60 transition-colors`}
     >
       <span className={`block w-1 shrink-0 ${accentClass}`} />
@@ -607,7 +607,7 @@ function DivergencePanel({
                   </span>
                   . Started {fmtAgo(openEvent.start_time)} at finalized block{' '}
                   <Link
-                    href={`/block/${openEvent.start_finalized_height}`}
+                    href={`/block/${openEvent.start_finalized_height}`} prefetch={false}
                     className="text-cipher-gold hover:underline"
                   >
                     #{openEvent.start_finalized_height.toLocaleString()}
@@ -618,7 +618,7 @@ function DivergencePanel({
                 <>
                   We&apos;ve diverged at finalized block{' '}
                   <Link
-                    href={`/block/${recurringHeight[0]}`}
+                    href={`/block/${recurringHeight[0]}`} prefetch={false}
                     className="text-cipher-gold hover:underline"
                   >
                     #{recurringHeight[0].toLocaleString()}
@@ -661,7 +661,7 @@ function DivergencePanel({
                   <td className="py-2 pr-4 text-secondary">{fmtAgo(e.start_time)}</td>
                   <td className="py-2 pr-4">
                     <Link
-                      href={`/block/${e.start_finalized_height}`}
+                      href={`/block/${e.start_finalized_height}`} prefetch={false}
                       className="text-cipher-gold hover:underline"
                     >
                       #{e.start_finalized_height.toLocaleString()}
diff --git a/components/GovernanceBanner.tsx b/components/GovernanceBanner.tsx
index ec116f9d..8c8344ee 100644
--- a/components/GovernanceBanner.tsx
+++ b/components/GovernanceBanner.tsx
@@ -4,6 +4,7 @@ import Link from 'next/link';
 import { useEffect, useRef, useState } from 'react';
 import { isMainnet, isCrosslink, NETWORK } from '@/lib/config';
 import type { Announcement } from '@/lib/governance';
+import type { AnnouncementSnapshot } from '@/lib/governance-announcement';
 import { useApiQuery } from '@/hooks/useApiQuery';
 import { readUpgradeSnapshot, estimateBlockArrival, formatUpgradeTime } from '@/lib/network-upgrades';
 
@@ -34,20 +35,46 @@ export function GovernanceBanner() {
   useEffect(() => {
     if (!isMainnet || isCrosslink) return;
     const controller = new AbortController();
+    let inFlight = false;
+    let expiryTimer: ReturnType<typeof setTimeout> | undefined;
     const refresh = async () => {
-      if (document.visibilityState !== 'visible') return;
+      if (document.visibilityState !== 'visible' || inFlight) return;
+      inFlight = true;
+      const startedAt = performance.now();
       try {
         const response = await fetch('/api/governance/announcement', { signal: AbortSignal.any([controller.signal, AbortSignal.timeout(10000)]) });
         if (!response.ok) throw new Error('Unavailable');
-        const { announcement: next } = await response.json() as { announcement: Announcement | null };
+        const { announcement: next, generatedAt, nextChangeAt } = await response.json() as AnnouncementSnapshot;
         if (controller.signal.aborted) return;
+        clearTimeout(expiryTimer);
+        // A CDN hit must retain the original deadline. Account for its Age and
+        // transfer time as well as the wall clock, so polling cannot extend a
+        // closing vote or a results announcement past its known window.
+        const age = Math.max(0, Number(response.headers.get('Age')) || 0) * 1000;
+        const remaining = nextChangeAt === null ? null : Math.min(
+          nextChangeAt - Date.now(),
+          nextChangeAt - generatedAt - age - (performance.now() - startedAt),
+        );
+        if (remaining !== null && (!Number.isFinite(remaining) || remaining <= 0)) {
+          setAnnouncement(null);
+          return;
+        }
         setAnnouncement(next);
-      } catch { if (!controller.signal.aborted) setAnnouncement(null); }
+        if (remaining !== null) expiryTimer = setTimeout(() => {
+          setAnnouncement(null);
+          void refresh();
+        }, Math.min(remaining, 2_147_483_647));
+      } catch {
+        if (!controller.signal.aborted) {
+          clearTimeout(expiryTimer);
+          setAnnouncement(null);
+        }
+      } finally { inFlight = false; }
     };
     void refresh();
     const timer = setInterval(() => void refresh(), 60_000);
     document.addEventListener('visibilitychange', refresh);
-    return () => { controller.abort(); clearInterval(timer); document.removeEventListener('visibilitychange', refresh); };
+    return () => { controller.abort(); clearInterval(timer); clearTimeout(expiryTimer); document.removeEventListener('visibilitychange', refresh); };
   }, []);
   useEffect(() => {
     const element = ref.current;
@@ -60,7 +87,7 @@ export function GovernanceBanner() {
   if (!visible || !displayed) return null;
   return <div ref={ref} role="region" aria-label={pending ? 'NU7 activation countdown' : 'Governance announcement'} className="ironwood-banner sticky top-[calc(var(--app-nav-height,4rem)+var(--app-stats-height,2.75rem))] z-40 border-b border-cipher-border/50 backdrop-blur-xl">
     <div className="relative mx-auto flex min-h-12 max-w-7xl items-center justify-center px-4 pr-12 py-2.5 sm:px-12">
-      <Link href={displayed.href} className={pending ? 'group flex items-center gap-3' : 'text-center font-mono text-xs text-brand-gold hover:underline'}>
+      <Link href={displayed.href} prefetch={false} className={pending ? 'group flex items-center gap-3' : 'text-center font-mono text-xs text-brand-gold hover:underline'}>
         {pending ? <>
           <span aria-hidden="true" className="flex h-8 w-8 shrink-0 items-center justify-center rounded-lg border border-cipher-gold/20 bg-cipher-gold/10 text-cipher-gold">
             <svg className="h-4 w-4" fill="none" viewBox="0 0 24 24" stroke="currentColor"><path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M13 10V3L4 14h7v7l9-11h-7z" /></svg>
diff --git a/components/RecentBlocks.tsx b/components/RecentBlocks.tsx
index 8bf001af..67e7c837 100644
--- a/components/RecentBlocks.tsx
+++ b/components/RecentBlocks.tsx
@@ -36,7 +36,7 @@ export const RecentBlocks = memo(function RecentBlocks({ footer }: { footer?: Re
                 style={{ animationDelay: `${i * 30}ms` }}
               >
                 <td className="px-4 sm:px-5 h-12 border-b border-cipher-border">
-                  <Link href={`/block/${block.height}`} className="font-mono text-sm font-medium text-primary group-hover:text-primary transition-colors tabular-nums">
+                  <Link href={`/block/${block.height}`} prefetch={false} className="font-mono text-sm font-medium text-primary group-hover:text-primary transition-colors tabular-nums">
                     #{block.height.toLocaleString()}
                   </Link>
                 </td>
diff --git a/components/RecentReorgs.tsx b/components/RecentReorgs.tsx
index 5464180a..22bb5aca 100644
--- a/components/RecentReorgs.tsx
+++ b/components/RecentReorgs.tsx
@@ -114,7 +114,7 @@ export const RecentReorgs = memo(function RecentReorgs({ footer }: { footer?: Re
                 style={{ animationDelay: `${i * 30}ms` }}
               >
                 <td className="px-4 sm:px-5 h-12 border-b border-cipher-border">
-                  <Link href={`/block/${fork.forkHeight}`} className="font-mono text-sm font-medium text-primary hover:underline transition-colors tabular-nums">
+                  <Link href={`/block/${fork.forkHeight}`} prefetch={false} className="font-mono text-sm font-medium text-primary hover:underline transition-colors tabular-nums">
                     #{fork.forkHeight.toLocaleString()}
                   </Link>
                 </td>
diff --git a/components/RiskyTxCard.tsx b/components/RiskyTxCard.tsx
index 7f13b406..c154fd68 100644
--- a/components/RiskyTxCard.tsx
+++ b/components/RiskyTxCard.tsx
@@ -15,7 +15,7 @@ export function RiskyTxCard({ tx }: { tx: RiskyTransaction }) {
     <RoundTripFlow tx={tx} />
     <ScoreEvidence rows={[{ label: 'Amount similarity', value: tx.scoreBreakdown.amountSimilarity }, { label: 'Time proximity', value: tx.scoreBreakdown.timeProximity }, { label: 'Amount rarity', value: tx.scoreBreakdown.amountRarity }, { label: 'Distinctive amount', value: tx.scoreBreakdown.weirdAmount }]} ambiguity={tx.ambiguityScore} margin={tx.confidenceMargin}>
       <p className="text-xs text-muted">Amounts describe each event’s public pool flow, not a verified payment between the listed addresses.</p>
-      <div className="flex flex-wrap gap-4 text-xs text-secondary"><Link className="underline underline-offset-4" href={`/block/${tx.shieldHeight}`}>Shielding block {tx.shieldHeight.toLocaleString()}</Link><Link className="underline underline-offset-4" href={`/block/${tx.deshieldHeight}`}>Deshielding block {tx.deshieldHeight.toLocaleString()}</Link></div>
+      <div className="flex flex-wrap gap-4 text-xs text-secondary"><Link className="underline underline-offset-4" href={`/block/${tx.shieldHeight}`} prefetch={false}>Shielding block {tx.shieldHeight.toLocaleString()}</Link><Link className="underline underline-offset-4" href={`/block/${tx.deshieldHeight}`} prefetch={false}>Deshielding block {tx.deshieldHeight.toLocaleString()}</Link></div>
     </ScoreEvidence>
   </article>;
 }
diff --git a/components/ask/AskBlocks.tsx b/components/ask/AskBlocks.tsx
index 9db78589..61d0f421 100644
--- a/components/ask/AskBlocks.tsx
+++ b/components/ask/AskBlocks.tsx
@@ -3,7 +3,7 @@ import type { AskBlocks as BlockResult } from '@/lib/ask/chat';
 
 export function AskBlocks({ result, expanded = false }: { result?: BlockResult; expanded?: boolean }) {
   if (!result) return null;
-  if (result.status === 'orphaned' && result.query.identifier) return <Link href={`/block/${result.query.identifier}`} className="mt-3 block text-sm text-cipher-gold hover:underline">Inspect orphaned block ↗</Link>;
+  if (result.status === 'orphaned' && result.query.identifier) return <Link href={`/block/${result.query.identifier}`} prefetch={false} className="mt-3 block text-sm text-cipher-gold hover:underline">Inspect orphaned block ↗</Link>;
   if (!result.rows.length) return null;
   return <details open={expanded || result.rows.length === 1} className="mt-4 rounded-lg border border-cipher-border p-3 text-sm">
     <summary className="cursor-pointer text-cipher-gold">{result.rows.length === 1 ? 'Block details' : `${result.rows.length} latest indexed blocks · unfiltered`}</summary>
diff --git a/components/ask/AskTransfers.tsx b/components/ask/AskTransfers.tsx
index 65e96a56..31a64856 100644
--- a/components/ask/AskTransfers.tsx
+++ b/components/ask/AskTransfers.tsx
@@ -15,7 +15,7 @@ export function AskTransfers({ result }: { result?: TransferResult }) {
       {group.kind === 'largest' && !result.complete ? <p className="text-sm text-muted">The full window could not be checked. No largest ranking is shown.</p> : !group.rows.length ? <p className="text-sm text-muted">No matching indexed transactions in this window.</p> : <div className="overflow-x-auto rounded-lg border border-cipher-border"><table className="w-full text-left text-xs">
         <caption className="sr-only">{group.kind} public {result.direction} transactions in the stated UTC window</caption>
         <thead className="border-b border-cipher-border text-muted"><tr><th scope="col" className="p-3">Transaction</th><th scope="col" className="p-3">ZEC</th><th scope="col" className="p-3">Time (UTC)</th><th scope="col" className="p-3">Pool</th></tr></thead>
-        <tbody>{group.rows.map(row => <tr key={row.txid} className="border-b border-cipher-border last:border-0"><td className="p-3"><Link href={`/tx/${row.txid}`} title={row.txid} className="font-mono text-cipher-gold hover:underline">{row.txid.slice(0, 8)}…{row.txid.slice(-6)}</Link></td><td className="whitespace-nowrap p-3 font-mono tabular-nums">{amount(row.amountZat)}</td><td className="whitespace-nowrap p-3 text-secondary">{utc(row.blockTime)}</td><td className="p-3 capitalize text-secondary">{row.pools.join(', ')}</td></tr>)}</tbody>
+        <tbody>{group.rows.map(row => <tr key={row.txid} className="border-b border-cipher-border last:border-0"><td className="p-3"><Link href={`/tx/${row.txid}`} prefetch={false} title={row.txid} className="font-mono text-cipher-gold hover:underline">{row.txid.slice(0, 8)}…{row.txid.slice(-6)}</Link></td><td className="whitespace-nowrap p-3 font-mono tabular-nums">{amount(row.amountZat)}</td><td className="whitespace-nowrap p-3 text-secondary">{utc(row.blockTime)}</td><td className="p-3 capitalize text-secondary">{row.pools.join(', ')}</td></tr>)}</tbody>
       </table></div>}
     </section>)}
     <p className="text-caption text-muted">Retrieved {utc(result.retrievedAt)} UTC. Public transaction flow amounts.{result.groups.some(group => group.rows.some(row => row.amountAuthority === 'legacy-reported-zec')) ? ' Amounts use the source’s reported ZEC values.' : ''}</p>
diff --git a/components/network/NetworkAccounting.tsx b/components/network/NetworkAccounting.tsx
index 7fedd623..5d6c2834 100644
--- a/components/network/NetworkAccounting.tsx
+++ b/components/network/NetworkAccounting.tsx
@@ -73,7 +73,7 @@ export function NetworkAccounting() {
   const bucketLabel = selected ? selected.bucketSeconds < 3600 ? `${selected.bucketSeconds/60}-minute` : selected.bucketSeconds < 86400
     ? `${Number((selected.bucketSeconds/3600).toFixed(1))}-hour` : `${Number((selected.bucketSeconds/86400).toFixed(1))}-day` : '';
   return <section id="nu7-accounting" className="network-section mt-5" aria-label="NU7 network accounting"><Card className="card-static"><CardBody>
-    <SectionHeader label="NU7_ACCOUNTING" actions={block && <Link href={`/block/${block.height}`}
+    <SectionHeader label="NU7_ACCOUNTING" actions={block && <Link href={`/block/${block.height}`} prefetch={false}
       title={`Latest indexed canonical block ${block.height.toLocaleString('en-US')}`}
       className="inline-flex items-center gap-1 rounded-full border border-cipher-border px-2.5 py-1 text-caption text-muted font-mono hover:text-primary">
       Block #{block.height.toLocaleString('en-US')} <span aria-hidden="true">↗</span>
diff --git a/components/network/RecentBlocksTable.tsx b/components/network/RecentBlocksTable.tsx
index 3153a384..f3953c11 100644
--- a/components/network/RecentBlocksTable.tsx
+++ b/components/network/RecentBlocksTable.tsx
@@ -26,7 +26,7 @@ const columns: DataTableColumn<RecentBlock>[] = [
     header: 'Block',
     skeletonWidth: 'w-24',
     cell: (b) => (
-      <Link href={`/block/${b.height}`} className="font-mono text-sm text-cipher-gold hover:underline">
+      <Link href={`/block/${b.height}`} prefetch={false} className="font-mono text-sm text-cipher-gold hover:underline">
         {b.height.toLocaleString()}
       </Link>
     ),
diff --git a/components/ui/HashLink.tsx b/components/ui/HashLink.tsx
index 8c641102..950d1660 100644
--- a/components/ui/HashLink.tsx
+++ b/components/ui/HashLink.tsx
@@ -15,6 +15,9 @@ function truncate(value: string, lead: number, tail: number): string {
  * link, and an optional one-click copy button. Use everywhere instead of
  * hand-rolled `slice(0, 8)}...{slice(-6)` so truncation and styling stay
  * identical across the app.
+ *
+ * Fetch linked detail pages on navigation. Lists contain many unique
+ * identifiers, so viewport prefetch would render pages visitors never open.
  */
 export function HashLink({
   value,
@@ -71,6 +74,7 @@ export function HashLink({
   const text = href ? (
     <Link
       href={href}
+      prefetch={false}
       title={value}
       className={linkClassName ?? `font-mono text-xs text-primary ${hover} transition-colors truncate ${full ? 'break-all' : ''}`}
     >
diff --git a/lib/governance-announcement.ts b/lib/governance-announcement.ts
new file mode 100644
index 00000000..268f06cf
--- /dev/null
+++ b/lib/governance-announcement.ts
@@ -0,0 +1,46 @@
+import { GRANTS, catalogIsStale, isGrantsRound, selectAnnouncement, type Announcement, type Catalog } from './governance';
+
+const CATALOG_REFRESH_MS = 60_000;
+const CATALOG_MAX_AGE_MS = 10 * 60_000;
+const RESULTS_WINDOW_MS = 5 * 86_400_000;
+
+export type AnnouncementSnapshot = {
+  announcement: Announcement | null;
+  generatedAt: number;
+  nextChangeAt: number | null;
+};
+
+export function buildAnnouncementSnapshot(catalog: Catalog, now: number) {
+  // Include every clock-driven selection boundary, including a currently empty
+  // banner becoming eligible. Only a new catalog may announce a vote opening.
+  const boundaries = [catalog.checkedAt + CATALOG_MAX_AGE_MS + 1];
+  if (!catalog.votes.some(vote => isGrantsRound(vote.round))) {
+    const opening = Date.parse(`${GRANTS.opensOn}T00:00:00Z`);
+    boundaries.push(opening - 7 * 86_400_000, opening);
+  }
+  for (const vote of catalog.votes) {
+    if (vote.state === 'active' || vote.state === 'results') boundaries.push(vote.round.vote_end_time * 1000);
+    if (vote.state === 'results') boundaries.push(vote.round.vote_end_time * 1000 + RESULTS_WINDOW_MS);
+  }
+  const futureBoundaries = boundaries.filter(time => Number.isFinite(time) && time > now);
+  const nextChangeAt = futureBoundaries.length ? Math.min(...futureBoundaries) : null;
+  // Do not stack a fresh CDN minute on top of the catalog's existing minute.
+  // A stale catalog can trigger its own refresh but cannot seed another CDN TTL.
+  const ttl = catalogIsStale(catalog, now) ? 0 : Math.max(0, Math.floor(Math.min(
+    CATALOG_REFRESH_MS,
+    catalog.checkedAt + CATALOG_REFRESH_MS - now,
+    nextChangeAt === null ? CATALOG_REFRESH_MS : nextChangeAt - now,
+  ) / 1000));
+  const snapshot: AnnouncementSnapshot = { announcement: selectAnnouncement(catalog, now), generatedAt: now, nextChangeAt };
+  return { snapshot, ttl };
+}
+
+export function announcementCacheHeaders(ttl: number) {
+  const cdn = ttl > 0 ? `public, s-maxage=${ttl}, must-revalidate` : 'no-store';
+  return {
+    'Cache-Control': ttl > 0 ? 'public, max-age=0, must-revalidate' : 'no-store',
+    'CDN-Cache-Control': cdn,
+    'Vercel-CDN-Cache-Control': cdn,
+    'X-Robots-Tag': 'noindex, follow',
+  };
+}
diff --git a/package.json b/package.json
index f7d4cfdc..356b9bfe 100644
--- a/package.json
+++ b/package.json
@@ -32,7 +32,7 @@
     "test:route-cache-build": "node --test server/tests/next-route-cache-build.test.js",
     "test:inbox-scan": "node --test server/tests/inbox-scan.test.js server/tests/scan-worker-pool.test.js server/api/test/scan-pipeline.test.js server/api/test/scan-cache.test.js server/api/test/scan-stream.test.js && cargo test --manifest-path wasm/Cargo.toml --lib",
     "test:live-refresh": "node --test server/tests/live-refresh.test.js server/tests/relative-time.test.js server/tests/api-query-freshness.test.js server/tests/network-snapshot.test.js server/tests/network-accounting-visibility.test.js server/tests/privacy-trend-dates.test.js",
-    "test:frontend": "node --test server/tests/crosslink-observations-ui.test.js server/tests/valuation-context.test.js server/tests/address-pagination-client.test.js server/tests/newsletter-security.test.js server/tests/name-rendering.test.js server/tests/http-status-boundaries.test.js server/tests/chart-sharing.test.js server/tests/redesign-data-boundaries.test.js server/tests/chart-catalog.test.js server/tests/block-timing.test.js server/tests/coinbase-message.test.js server/tests/network-upgrades.test.js server/tests/browser-decoder.test.js server/tests/hashrate-display.test.js server/tests/reorg-display.test.js && npm run test:live-refresh && npm run test:sitemap-security && npm run test:performance && npm run test:ttfb-probe && npm run test:isr-warmup && npm run test:revalidate-security && NODE_PATH=$PWD/server/api/node_modules node --test server/tests/address-labels-resilience.test.js && npm run test:brand && npm run test:v1-frontend && node --test server/tests/address-connections.test.js && npm run test:attestations && npm run test:nu7-results && npm run test:governance && node --test server/tests/network-issuance-ui.test.js && node --test server/tests/launch-copy-privacy.test.js",
+    "test:frontend": "node --test server/tests/detail-link-prefetch.test.js server/tests/orphan-ssr-replacement.test.js server/tests/crosslink-observations-ui.test.js server/tests/valuation-context.test.js server/tests/address-pagination-client.test.js server/tests/newsletter-security.test.js server/tests/name-rendering.test.js server/tests/http-status-boundaries.test.js server/tests/chart-sharing.test.js server/tests/redesign-data-boundaries.test.js server/tests/chart-catalog.test.js server/tests/block-timing.test.js server/tests/coinbase-message.test.js server/tests/network-upgrades.test.js server/tests/browser-decoder.test.js server/tests/hashrate-display.test.js server/tests/reorg-display.test.js && npm run test:live-refresh && npm run test:sitemap-security && npm run test:performance && npm run test:ttfb-probe && npm run test:isr-warmup && npm run test:revalidate-security && NODE_PATH=$PWD/server/api/node_modules node --test server/tests/address-labels-resilience.test.js && npm run test:brand && npm run test:v1-frontend && node --test server/tests/address-connections.test.js && npm run test:attestations && npm run test:nu7-results && npm run test:governance && node --test server/tests/network-issuance-ui.test.js && node --test server/tests/launch-copy-privacy.test.js",
     "test:server-regressions": "NODE_PATH=$PWD/server/api/node_modules node --test server/tests/crosslink-roster.test.js server/tests/hashrate.test.js server/tests/reorg-api.test.js server/tests/orphan-rates.test.js server/tests/blocks-orphan-batch.test.js server/tests/tx-detail-parallel.test.js server/tests/tx-mempool-cache.test.js server/tests/migration-activity-summary.test.js server/tests/blend-check-batch.test.js server/tests/db-pool-deadlines.test.js server/tests/safe-log.test.js server/tests/ironwood-accounting.test.js server/tests/exposure-consumers.test.js server/tests/network-halving.test.js server/tests/network-issuance.test.js server/tests/supply-history-backfill.test.js server/tests/braces-security.test.js server/tests/network-schedule.test.js server/tests/network-block-time.test.js server/tests/mining-metrics.test.js server/tests/network-issuance-curve.test.js server/tests/network-fee-history.test.js server/tests/network-readiness.test.js server/tests/network-accounting-period.test.js server/tests/rpc-cookie-rotation.test.js server/tests/peer-client.test.js server/tests/node-census.test.js server/tests/node-census-postgres.test.js server/tests/privacy-score.test.js server/tests/privacy-stats-snapshot.test.js server/tests/utxo-age.test.js server/tests/signal-telegram.test.js server/tests/analytics-history.test.js server/tests/mining-attribution-repair.test.js server/tests/analytics-history-routes.test.js server/tests/crosschain-v2.test.js server/tests/crosschain-date-pages.test.js server/tests/crosschain-maintenance-budget.test.js server/tests/near-provider-budget.test.js server/tests/address-pagination.test.js server/tests/address-cursor-postgres.test.js && npm run test:error-message-leakage",
     "verify:fast": "npm run lint && tsc --noEmit",
     "verify:frontend": "npm run verify:fast && npm run test:frontend && CIPHERSCAN_ALLOW_BUILD_UPSTREAM_FALLBACK=1 npm run build && npm run test:route-cache-build",
@@ -56,7 +56,7 @@
     "verify:homepage:live": "node scripts/verify-homepage-live-api.mjs",
     "verify:homepage": "node scripts/verify-homepage-first-render.mjs",
     "test:nu7-results": "node --test server/tests/nu7-results.test.js",
-    "test:governance": "node --test server/tests/governance.test.js",
+    "test:governance": "node --test server/tests/governance.test.js server/tests/governance-announcement-cache.test.js",
     "test:activity": "NODE_PATH=$PWD/server/api/node_modules node --test server/tests/activity-milestones.test.js server/tests/activity-postgres.test.js",
     "test:hashrate-postgres": "NODE_PATH=$PWD/server/api/node_modules node --test server/tests/hashrate-postgres.test.js",
     "test:analytics-history": "NODE_PATH=$PWD/server/api/node_modules node --test server/tests/analytics-history.test.js server/tests/analytics-history-routes.test.js",
diff --git a/proxy.ts b/proxy.ts
index 0de3962a..98541bae 100644
--- a/proxy.ts
+++ b/proxy.ts
@@ -25,7 +25,7 @@ setInterval(() => {
   }
 }, 5 * 60 * 1000);
 
-function handleApiRateLimit(request: NextRequest): NextResponse {
+function handleApiRateLimit(request: NextRequest, includeQuotaHeaders = true): NextResponse {
   const ip =
     request.headers.get('x-forwarded-for')?.split(',')[0]?.trim() ||
     request.headers.get('x-real-ip') ||
@@ -63,6 +63,10 @@ function handleApiRateLimit(request: NextRequest): NextResponse {
   }
 
   const response = NextResponse.next();
+  // Shared CDN responses must not replay the first visitor's per-IP quota.
+  // Keep enforcement above; a rejected request still receives its own quota
+  // and Retry-After headers from the uncached 429 response.
+  if (!includeQuotaHeaders) return response;
   const remaining = Math.max(0, RATE_LIMIT.maxRequests - userData.count);
 
   response.headers.set('X-RateLimit-Limit', RATE_LIMIT.maxRequests.toString());
@@ -117,6 +121,23 @@ export async function proxy(request: NextRequest) {
       headers: { 'Content-Type': 'text/html; charset=utf-8', 'Cache-Control': 'no-store', 'X-Robots-Tag': 'noindex, follow' },
     });
   }
+  // One cache identity per identifier. These aliases already share canonical
+  // metadata, but otherwise cause separate on-demand page generations. Keep
+  // block-hash lookups (including persistent orphans) distinct from heights.
+  const detailPath = request.nextUrl.pathname.match(/^\/(tx|block)\/([^/]+)$/);
+  if (detailPath) {
+    const [, kind, identifier] = detailPath;
+    const isHash = /^[a-fA-F0-9]{64}$/.test(identifier);
+    const isHeight = kind === 'block' && /^\d+$/.test(identifier)
+      && Number(identifier) <= 100_000_000;
+    const normalized = isHash ? identifier.toLowerCase()
+      : isHeight ? String(Number(identifier)) : identifier;
+    if (normalized !== identifier) {
+      const url = request.nextUrl.clone();
+      url.pathname = `/${kind}/${normalized}`;
+      return NextResponse.redirect(url, 308);
+    }
+  }
   // Keep filtered archives dynamic and the unfiltered list on its ISR route.
   // Vercel permits at most 16 has/missing conditions per static routing rule.
   if (request.nextUrl.pathname === '/blocks') {
@@ -180,7 +201,7 @@ export async function proxy(request: NextRequest) {
   const { pathname } = request.nextUrl;
 
   if (pathname.startsWith('/api/')) {
-    return handleApiRateLimit(request);
+    return handleApiRateLimit(request, pathname !== '/api/governance/announcement');
   }
 
   // Block pages take their CDN lifetime from ISR (getBlockResolution): one
@@ -190,5 +211,6 @@ export async function proxy(request: NextRequest) {
 }
 
 export const config = {
-  matcher: ['/name/:path*', '/api/:path*', '/block/:path*', '/blocks', '/governance/:path*', '/charts/:slug'],
+  // Canonical lowercase tx URLs bypass Proxy; only uppercase aliases need it.
+  matcher: ['/name/:path*', '/api/:path*', '/tx/:txid((?=[a-fA-F0-9]{0,63}[A-F])[a-fA-F0-9]{64})', '/block/:path*', '/blocks', '/governance/:path*', '/charts/:slug'],
 };
diff --git a/server/tests/detail-link-prefetch.test.js b/server/tests/detail-link-prefetch.test.js
new file mode 100644
index 00000000..5687ba61
--- /dev/null
+++ b/server/tests/detail-link-prefetch.test.js
@@ -0,0 +1,103 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const vm = require('node:vm');
+const ts = require('typescript');
+const React = require('react');
+const { renderToStaticMarkup } = require('react-dom/server');
+
+const root = path.resolve(__dirname, '../..');
+
+function load(relativePath, dependencies) {
+  const exports = {};
+  const source = fs.readFileSync(path.join(root, relativePath), 'utf8');
+  vm.runInNewContext(ts.transpileModule(source, {
+    compilerOptions: {
+      module: ts.ModuleKind.CommonJS,
+      target: ts.ScriptTarget.ES2022,
+      jsx: ts.JsxEmit.ReactJSX,
+      esModuleInterop: true,
+    },
+  }).outputText, {
+    exports,
+    require(name) {
+      if (name in dependencies) return dependencies[name];
+      if (['react/jsx-runtime', 'next/link'].includes(name)) return require(name);
+      throw new Error(`Unexpected dependency ${name}`);
+    },
+  });
+  return exports;
+}
+
+function filesUnder(directory) {
+  return fs.readdirSync(directory, { withFileTypes: true }).flatMap(entry => {
+    const file = path.join(directory, entry.name);
+    return entry.isDirectory() ? filesUnder(file) : file.endsWith('.tsx') ? [file] : [];
+  });
+}
+
+test('detail links retain normal navigation without speculative viewport requests', () => {
+  let checked = 0;
+  const violations = [];
+  for (const file of ['app', 'components'].flatMap(directory => filesUnder(path.join(root, directory)))) {
+    const source = ts.createSourceFile(file, fs.readFileSync(file, 'utf8'), ts.ScriptTarget.Latest, true, ts.ScriptKind.TSX);
+    function visit(node) {
+      if ((ts.isJsxOpeningElement(node) || ts.isJsxSelfClosingElement(node)) && node.tagName.getText(source) === 'Link') {
+        const attributes = node.attributes.properties;
+        const href = attributes.find(attribute => ts.isJsxAttribute(attribute) && attribute.name.getText(source) === 'href');
+        // Cover literal URLs, templates and conditional canonical/orphan targets.
+        if (href && /[`"']\/(block|tx|address)\//.test(href.getText(source))) {
+          checked++;
+          const prefetch = attributes.find(attribute => ts.isJsxAttribute(attribute) && attribute.name.getText(source) === 'prefetch');
+          const disabled = prefetch?.initializer && ts.isJsxExpression(prefetch.initializer)
+            && prefetch.initializer.expression?.kind === ts.SyntaxKind.FalseKeyword;
+          if (!disabled) {
+            const line = source.getLineAndCharacterOfPosition(node.getStart(source)).line + 1;
+            violations.push(`${path.relative(root, file)}:${line}`);
+          }
+        }
+      }
+      ts.forEachChild(node, visit);
+    }
+    visit(source);
+  }
+  assert.ok(checked > 50, 'the audit must cover actual explorer detail links');
+  assert.deepEqual(violations, [], 'detail pages should be requested on navigation, not just because a list is visible');
+});
+
+test('shared hash links server-render crawlable hrefs and full identifiers', () => {
+  const { HashLink } = load('components/ui/HashLink.tsx', {
+    '@/components/CopyButton': { CopyButton: () => null },
+  });
+  for (const [prefix, identifier] of [['tx', 'a'.repeat(64)], ['block', '3500000'], ['address', 't1full-public-address']]) {
+    const href = `/${prefix}/${identifier}`;
+    const element = HashLink({ value: identifier, href, copy: false });
+    const link = element.props.children[0];
+    assert.equal(link.props.prefetch, false, 'shared tables and CopyableHash use navigation-only data links');
+    const html = renderToStaticMarkup(element);
+    assert.ok(html.includes(`href="${href}"`), html);
+    assert.ok(html.includes(`title="${identifier}"`), 'the complete identifier remains in server HTML');
+    assert.ok(!html.includes('nofollow'), 'crawler discovery remains available');
+  }
+  const plain = renderToStaticMarkup(React.createElement(HashLink, { value: 'b'.repeat(64), copy: false }));
+  assert.ok(plain.includes('<code'));
+  assert.ok(!plain.includes('<a'), 'unlinked identifiers remain plain text');
+});
+
+test('labeled address components retain crawlable addresses and link intent', () => {
+  const { AddressWithLabel, AddressDisplay } = load('components/AddressWithLabel.tsx', {
+    '@/lib/address-labels': { useAddressLabel: () => ({ label: 'Public miner', description: 'Public attribution', isOfficial: true }) },
+  });
+  const address = 't1full-public-miner-address';
+  for (const Component of [AddressWithLabel, AddressDisplay]) {
+    const element = Component({ address });
+    assert.equal(element.props.href, `/address/${address}`);
+    assert.equal(element.props.prefetch, false);
+    const html = renderToStaticMarkup(element);
+    assert.ok(html.includes(`href="/address/${address}"`));
+    assert.ok(html.includes('Public miner'));
+  }
+  const plain = renderToStaticMarkup(React.createElement(AddressWithLabel, { address, linkable: false }));
+  assert.ok(!plain.includes('<a'), 'non-linkable addresses stay non-interactive');
+});
diff --git a/server/tests/governance-announcement-cache.test.js b/server/tests/governance-announcement-cache.test.js
new file mode 100644
index 00000000..a033a118
--- /dev/null
+++ b/server/tests/governance-announcement-cache.test.js
@@ -0,0 +1,227 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const vm = require('node:vm');
+const ts = require('typescript');
+
+function load(file, dependencies = {}, globals = {}) {
+  const exports = {};
+  vm.runInNewContext(ts.transpileModule(fs.readFileSync(file, 'utf8'), {
+    compilerOptions: { target: ts.ScriptTarget.ES2022, module: ts.ModuleKind.CommonJS, jsx: ts.JsxEmit.ReactJSX },
+  }).outputText, { exports, atob, URL, Response, require: name => dependencies[name] ?? require(name), ...globals });
+  return exports;
+}
+const nu7 = load('lib/nu7-vote-results.ts');
+const model = load('lib/governance.ts', { './nu7-vote-results': nu7 });
+const helpers = load('lib/governance-announcement.ts', { './governance': model });
+const now = Date.parse('2026-10-16T00:00:00Z');
+const Clock = class extends Date { static now() { return now; } };
+function vote(state, end = now + 3600_000, id = 'reviewed-vote') {
+  return { id, state, title: 'Reviewed vote', href: `/governance/${id}`, round: { vote_end_time: end / 1000, discussion_url: '' } };
+}
+function catalog(votes = [], checkedAt = now) { return { votes, checkedAt, unavailable: false }; }
+function route(network, data) {
+  let calls = 0;
+  return {
+    handler: load('app/api/governance/announcement/route.ts', {
+      '@/lib/governance-data': { getGovernanceCatalog: async () => { calls++; return data; } },
+      '@/lib/governance-announcement': helpers,
+      '@/lib/seo': { getNetwork: () => network },
+    }, { Date: Clock }).GET,
+    calls: () => calls,
+  };
+}
+
+test('mainnet shares fresh announcements at the CDN while browsers revalidate and APIs stay noindex', async () => {
+  const api = route('mainnet', catalog([vote('active')]));
+  const response = await api.handler();
+  const body = await response.json();
+  assert.equal(response.status, 200);
+  assert.equal(api.calls(), 1);
+  assert.equal(body.announcement.key, 'reviewed-vote:active');
+  assert.equal(body.generatedAt, now);
+  assert.equal(response.headers.get('Cache-Control'), 'public, max-age=0, must-revalidate');
+  for (const header of ['CDN-Cache-Control', 'Vercel-CDN-Cache-Control']) {
+    assert.equal(response.headers.get(header), 'public, s-maxage=60, must-revalidate');
+    assert.doesNotMatch(response.headers.get(header), /stale-while-revalidate|stale-if-error/);
+  }
+  assert.equal(response.headers.get('X-Robots-Tag'), 'noindex, follow');
+});
+
+test('testnet and Crosslink never fetch or expose mainnet governance', async () => {
+  for (const network of ['testnet', 'crosslink-testnet']) {
+    const api = route(network, catalog([vote('active')]));
+    const response = await api.handler();
+    assert.equal((await response.json()).announcement, null);
+    assert.equal(api.calls(), 0);
+    assert.equal(response.headers.get('X-Robots-Tag'), 'noindex, follow');
+  }
+});
+
+test('empty successful catalogs share null, but unavailable and stale catalogs never enter the CDN', async () => {
+  const empty = await route('mainnet', catalog()).handler();
+  assert.equal((await empty.json()).announcement, null);
+  assert.match(empty.headers.get('Vercel-CDN-Cache-Control'), /s-maxage=60/);
+  for (const data of [{ votes: [], checkedAt: 0, unavailable: true }, catalog([vote('active')], now - 600_001)]) {
+    const response = await route('mainnet', data).handler();
+    assert.equal((await response.json()).announcement, null);
+    for (const header of ['Cache-Control', 'CDN-Cache-Control', 'Vercel-CDN-Cache-Control']) assert.equal(response.headers.get(header), 'no-store');
+  }
+});
+
+test('CDN freshness uses the remaining catalog minute rather than adding another minute', () => {
+  assert.equal(helpers.buildAnnouncementSnapshot(catalog([], now - 45_250), now).ttl, 14);
+  for (const age of [60_000, 60_001, 300_000]) {
+    assert.equal(helpers.buildAnnouncementSnapshot(catalog([vote('active')], now - age), now).ttl, 0);
+  }
+});
+
+test('active voting closes at its deadline and CDN caching rounds down before the boundary', () => {
+  const closing = now + 10_250;
+  const data = catalog([vote('active', closing)]);
+  const before = helpers.buildAnnouncementSnapshot(data, now);
+  assert.equal(before.ttl, 10);
+  assert.equal(before.snapshot.nextChangeAt, closing);
+  assert.equal(before.snapshot.announcement.key, 'reviewed-vote:active');
+  assert.equal(helpers.buildAnnouncementSnapshot(data, closing - 250).ttl, 0);
+  assert.equal(helpers.buildAnnouncementSnapshot(data, closing).snapshot.announcement, null);
+});
+
+test('results and upcoming date-only notices transition without fabricating an opening or result', () => {
+  const expiry = now + 10_000;
+  const results = catalog([vote('results', expiry - 5 * 86_400_000)]);
+  assert.equal(helpers.buildAnnouncementSnapshot(results, now).snapshot.nextChangeAt, expiry);
+  assert.equal(helpers.buildAnnouncementSnapshot(results, expiry).snapshot.announcement, null);
+  const opening = Date.parse(`${model.GRANTS.opensOn}T00:00:00Z`);
+  const start = opening - 7 * 86_400_000;
+  const before = helpers.buildAnnouncementSnapshot(catalog([], start - 10_000), start - 10_000);
+  assert.equal(before.snapshot.announcement, null);
+  assert.equal(before.snapshot.nextChangeAt, start);
+  assert.equal(before.ttl, 10);
+  const during = helpers.buildAnnouncementSnapshot(catalog([], opening - 10_000), opening - 10_000);
+  assert.equal(during.snapshot.announcement.key, `${model.GRANTS.slug}:upcoming`);
+  assert.equal(during.snapshot.nextChangeAt, opening);
+  assert.equal(helpers.buildAnnouncementSnapshot(catalog([], opening), opening).snapshot.announcement, null);
+});
+
+function bannerHarness(responses, initialNow = now) {
+  const effects = [];
+  const updates = [];
+  const timeouts = new Map();
+  const intervals = new Map();
+  const listeners = new Map();
+  let clock = initialNow;
+  let nextTimer = 1;
+  let calls = 0;
+  let state = 0;
+  const FakeDate = class extends Date { static now() { return clock; } };
+  const component = load('components/GovernanceBanner.tsx', {
+    react: {
+      useState: value => { const index = state++; return [value, next => { if (index === 0) updates.push(next); }]; },
+      useRef: value => ({ current: value }), useEffect: effect => effects.push(effect),
+    },
+    'next/link': {}, '@/lib/config': { isMainnet: true, isCrosslink: false, NETWORK: 'mainnet' },
+    '@/hooks/useApiQuery': { useApiQuery: () => ({ data: null, error: null }) },
+    '@/lib/network-upgrades': { readUpgradeSnapshot: () => null },
+  }, {
+    Date: FakeDate, performance: { now: () => clock }, AbortController,
+    AbortSignal: { any: signals => signals[0], timeout: () => new AbortController().signal },
+    document: { visibilityState: 'visible', addEventListener: (key, fn) => listeners.set(key, fn), removeEventListener: key => listeners.delete(key) },
+    setTimeout: (fn, delay) => { const id = nextTimer++; timeouts.set(id, { fn, at: clock + delay }); return id; },
+    clearTimeout: id => timeouts.delete(id),
+    setInterval: (fn, delay) => { const id = nextTimer++; intervals.set(id, { fn, delay }); return id; },
+    clearInterval: id => intervals.delete(id),
+    fetch: async () => {
+      const response = responses[Math.min(calls++, responses.length - 1)];
+      if (response instanceof Error) throw response;
+      return response;
+    },
+  });
+  component.GovernanceBanner();
+  const cleanup = effects[1]();
+  return { updates, timeouts, intervals, cleanup, calls: () => calls, advance: value => { clock += value; },
+    tick: async () => { await new Promise(resolve => setImmediate(resolve)); } };
+}
+function response(snapshot, age = '0') {
+  return { ok: true, headers: new Headers({ Age: age }), json: async () => snapshot };
+}
+
+test('a cached banner clears at the known boundary, accounts for CDN Age, and keeps its minute poll', async () => {
+  const active = { key: 'vote:active', href: '/governance/vote', text: 'Voting is open' };
+  const initial = { announcement: active, generatedAt: now - 50_000, nextChangeAt: now + 10_000 };
+  const ended = { announcement: null, generatedAt: now + 10_000, nextChangeAt: null };
+  const banner = bannerHarness([response(initial, '50'), response(ended)]);
+  await banner.tick();
+  assert.equal(banner.updates.at(-1).key, active.key);
+  assert.equal([...banner.intervals.values()][0].delay, 60_000);
+  const expiry = [...banner.timeouts.values()][0];
+  assert.equal(expiry.at, now + 10_000);
+  banner.advance(10_000);
+  expiry.fn();
+  assert.equal(banner.updates.at(-1), null);
+  await banner.tick();
+  assert.equal(banner.calls(), 2);
+  assert.equal(banner.updates.at(-1), null);
+  banner.cleanup();
+  assert.equal(banner.timeouts.size, 0);
+  assert.equal(banner.intervals.size, 0);
+});
+
+test('expired CDN payloads and failed refreshes cannot retain actionable announcement text', async () => {
+  const active = { key: 'vote:active', href: '/governance/vote', text: 'Voting is open' };
+  // CDN age protects the deadline even when the browser wall clock is behind.
+  const expired = bannerHarness([response({ announcement: active, generatedAt: now - 60_000, nextChangeAt: now - 1 }, '61')], now - 30_000);
+  await expired.tick();
+  assert.equal(expired.updates.at(-1), null);
+  assert.equal(expired.timeouts.size, 0);
+  expired.cleanup();
+  const banner = bannerHarness([response({ announcement: active, generatedAt: now, nextChangeAt: now + 120_000 }), new Error('offline')]);
+  await banner.tick();
+  assert.equal(banner.updates.at(-1).key, active.key);
+  [...banner.intervals.values()][0].fn();
+  await banner.tick();
+  assert.equal(banner.updates.at(-1), null);
+  assert.equal(banner.timeouts.size, 0);
+  banner.cleanup();
+});
+
+test('a stale catalog with a distant deadline cannot overflow the browser timer into a refresh loop', async () => {
+  const stale = helpers.buildAnnouncementSnapshot(catalog([vote('active', now + 30 * 86_400_000)], now - 600_001), now);
+  assert.equal(stale.snapshot.announcement, null);
+  assert.equal(stale.ttl, 0);
+  const banner = bannerHarness([response(stale.snapshot)]);
+  await banner.tick();
+  assert.equal(banner.calls(), 1);
+  assert.equal(banner.updates.at(-1), null);
+  const timer = [...banner.timeouts.values()][0];
+  assert.equal(timer.at - now, 2_147_483_647, 'setTimeout must stay within the browser signed 32-bit limit');
+  assert.equal([...banner.intervals.values()][0].delay, 60_000);
+  banner.cleanup();
+});
+
+test('shared announcement responses omit per-IP quota headers while the same limit remains enforced', async () => {
+  const { NextRequest, NextResponse } = require('next/server');
+  const { proxy } = load('proxy.ts', {
+    'next/server': { NextResponse },
+    './lib/governance-request': {}, './lib/network': {}, './lib/chart-catalog': {}, './lib/name-validation': {},
+  }, { process: { env: { NODE_ENV: 'production' } }, setInterval: () => {} });
+  const request = path => new NextRequest(`https://zecblock.com${path}`, {
+    headers: { host: 'zecblock.com', 'x-forwarded-for': '192.0.2.123' },
+  });
+  for (let i = 0; i < 300; i++) {
+    const response = await proxy(request('/api/governance/announcement'));
+    assert.equal(response.headers.get('x-middleware-next'), '1');
+    for (const header of ['X-RateLimit-Limit', 'X-RateLimit-Remaining', 'X-RateLimit-Reset']) {
+      assert.equal(response.headers.get(header), null, 'shared responses must not cache a visitor-specific quota');
+    }
+  }
+  const limited = await proxy(request('/api/governance/announcement'));
+  assert.equal(limited.status, 429);
+  assert.equal(limited.headers.get('X-RateLimit-Remaining'), '0');
+  assert.ok(Number(limited.headers.get('Retry-After')) > 0);
+  const other = await proxy(new NextRequest('https://zecblock.com/api/revalidate', {
+    headers: { host: 'zecblock.com', 'x-forwarded-for': '192.0.2.124' },
+  }));
+  assert.equal(other.headers.get('X-RateLimit-Limit'), '300', 'other APIs retain their existing quota contract');
+  assert.equal(other.headers.get('X-RateLimit-Remaining'), '299');
+});
diff --git a/server/tests/next-route-cache-build.test.js b/server/tests/next-route-cache-build.test.js
index 393c2609..dcf7c581 100644
--- a/server/tests/next-route-cache-build.test.js
+++ b/server/tests/next-route-cache-build.test.js
@@ -62,3 +62,11 @@ test('detail routes retain on-demand static fallbacks for runtime ISR', () => {
 test('network snapshot retains five-minute ISR independently of live browser polling', () => {
   assert.equal(manifest.routes?.['/network']?.initialRevalidateSeconds, 300);
 });
+
+test('governance announcements compute clock boundaries at request time before entering the CDN', () => {
+  assert.equal(
+    manifest.routes?.['/api/governance/announcement'],
+    undefined,
+    'announcement selection must not become a static ISR response that outlives a known vote boundary',
+  );
+});
diff --git a/server/tests/orphan-ssr-replacement.test.js b/server/tests/orphan-ssr-replacement.test.js
new file mode 100644
index 00000000..56582ac6
--- /dev/null
+++ b/server/tests/orphan-ssr-replacement.test.js
@@ -0,0 +1,55 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const vm = require('node:vm');
+const ts = require('typescript');
+const React = require('react');
+const { renderToStaticMarkup } = require('react-dom/server');
+
+function load(file, dependencies = {}) {
+  const exports = {};
+  vm.runInNewContext(ts.transpileModule(fs.readFileSync(file, 'utf8'), {
+    compilerOptions: { module: ts.ModuleKind.CommonJS, jsx: ts.JsxEmit.ReactJSX },
+  }).outputText, { exports, URL, require: name => dependencies[name] ?? require(name) });
+  return exports;
+}
+const { BlockPageSkeleton } = load('app/block/[height]/components/BlockPageSkeleton.tsx', {
+  'next/link': { default: ({ children, prefetch, ...props }) => React.createElement('a', { ...props, 'data-prefetch': String(prefetch) }, children) },
+  '@/components/ui/EmptyState': { SkeletonTable: () => null },
+  '@/components/ui/Skeleton': { Skeleton: () => null },
+  '@/components/ui/Card': Object.fromEntries(['Card', 'CardHeader', 'CardBody'].map(name => [name, ({ children }) => React.createElement('div', null, children)])),
+  '@/components/ui/Badge': { Badge: ({ children }) => React.createElement('span', null, children) },
+  '@/lib/utils': { formatRelativeTime: () => '2 minutes ago' },
+  '@/lib/format-numbers': { formatBytesCompact: value => `${value} B` },
+});
+
+async function render(block) {
+  const page = load('app/block/[height]/page.tsx', {
+    '@/lib/api-client': {}, 'next/navigation': {},
+    '@/lib/seo': { getBlockResolution: async () => ({ state: 'found', block }), getBaseUrl: () => 'https://zecblock.com',
+      normalizeBlockIdentifier: value => value, BLOCK_HASH_PATTERN: /^[a-fA-F0-9]{64}$/ },
+    '@/lib/server-fetch': {}, '@/lib/isr-fallback': {}, '@/lib/network-upgrades-server': {}, '@/lib/network-upgrades': {}, './FutureBlockView': {},
+    './BlockPageClient': { default: props => React.createElement(BlockPageSkeleton, props) },
+  });
+  return renderToStaticMarkup(await page.default({ params: Promise.resolve({ height: block.hash }) }));
+}
+const orphan = { height: 100, hash: 'b'.repeat(64), isOrphaned: true, timestamp: 1792140000, transaction_count: 2, size: 1024 };
+
+test('orphan server HTML includes the verified canonical replacement link and retains the orphan identifier', async () => {
+  const html = await render({ ...orphan, canonicalBlock: { hash: 'a'.repeat(64) } });
+  assert.equal((html.match(/<h1(?:\s|>)/g) || []).length, 1);
+  assert.match(html, /Orphaned Zcash Block/);
+  assert.ok(html.includes(orphan.hash));
+  assert.match(html, /Canonical replacement at this height/);
+  assert.match(html, /href="\/block\/100"[^>]*data-prefetch="false"/);
+  assert.match(html, /Zcash block #100/);
+});
+
+test('server HTML never invents replacement discovery from an absent, malformed or identical hash', async () => {
+  for (const canonicalBlock of [null, {}, { hash: null }, { hash: '' }, { hash: 'bad' }, { hash: orphan.hash }, { hash: orphan.hash.toUpperCase() }]) {
+    const html = await render({ ...orphan, canonicalBlock });
+    assert.doesNotMatch(html, /Canonical replacement at this height|href="\/block\/100"/);
+  }
+  const canonical = await render({ ...orphan, isOrphaned: false, canonicalBlock: { hash: 'a'.repeat(64) } });
+  assert.doesNotMatch(canonical, /Canonical replacement at this height|href="\/block\/100"/);
+});
diff --git a/server/tests/reorg-display.test.js b/server/tests/reorg-display.test.js
index b1157714..b0d1f0fc 100644
--- a/server/tests/reorg-display.test.js
+++ b/server/tests/reorg-display.test.js
@@ -108,3 +108,48 @@ test('block list routing preserves every archive filter and only rewrites unfilt
     }
   }
 });
+
+test('identifier aliases redirect before SSR without changing network, query or orphan identity', async () => {
+  const { NextRequest, NextResponse } = require('next/server');
+  const { unstable_doesMiddlewareMatch } = require('next/experimental/testing/server');
+  const exports = {};
+  vm.runInNewContext(ts.transpileModule(fs.readFileSync('proxy.ts', 'utf8'), {
+    compilerOptions: { module: ts.ModuleKind.CommonJS },
+  }).outputText, { exports, URL, process: { env: { NODE_ENV: 'development' } }, setInterval: () => {},
+    require: name => ({
+      'next/server': { NextResponse },
+      './lib/governance-request': {},
+      './lib/network': {},
+    })[name],
+  });
+  for (const host of ['zecblock.com', 'testnet.zecblock.com', 'crosslink.zecblock.com']) {
+    for (const [alias, canonical] of [
+      [`/tx/${'Ab'.repeat(32)}`, `/tx/${'ab'.repeat(32)}`],
+      [`/block/${'Cd'.repeat(32)}`, `/block/${'cd'.repeat(32)}`],
+      ['/block/0003492072', '/block/3492072'],
+      ['/block/000', '/block/0'],
+    ]) {
+      const url = `https://${host}${alias}?utm_source=reference`;
+      assert.equal(unstable_doesMiddlewareMatch({ config: exports.config, nextConfig: {}, url }), true);
+      const response = await exports.proxy(new NextRequest(url));
+      assert.equal(response.status, 308);
+      assert.equal(response.headers.get('location'), `https://${host}${canonical}?utm_source=reference`);
+    }
+    const canonicalTx = `https://${host}/tx/${'ab'.repeat(32)}`;
+    assert.equal(unstable_doesMiddlewareMatch({ config: exports.config, nextConfig: {}, url: canonicalTx }), false,
+      'ordinary transaction views must not gain a paid Proxy invocation');
+    for (const identifier of ['A'.repeat(63), 'A'.repeat(65), `${'A'.repeat(64)}g`, `${'A'.repeat(8192)}g`]) {
+      assert.equal(unstable_doesMiddlewareMatch({ config: exports.config, nextConfig: {}, url: `https://${host}/tx/${identifier}` }), false,
+        'invalid lengths and long invalid input must not invoke the alias normalizer');
+    }
+    for (const identifier of ['3492072', 'cd'.repeat(32), '0'.repeat(64)]) {
+      const response = await exports.proxy(new NextRequest(`https://${host}/block/${identifier}`));
+      assert.equal(response.headers.get('location'), null, 'a canonical hash, including an orphan, stays a hash lookup');
+    }
+    for (const identifier of ['-01', '100000001', '000100000001', 'invalid']) {
+      const response = await exports.proxy(new NextRequest(`https://${host}/block/${identifier}`));
+      assert.equal(response.status, 404, 'normalization must not rescue an invalid identifier');
+      assert.equal(response.headers.get('location'), null);
+    }
+  }
+});