diff --git a/apps/publish/CLAUDE.md b/apps/publish/CLAUDE.md
index a81e747..3058040 100644
--- a/apps/publish/CLAUDE.md
+++ b/apps/publish/CLAUDE.md
@@ -205,11 +205,20 @@ CFP row is left out entirely where the destination would never ask.
 
 ## An invalid feed stops everything, before any destination
 
-`main.ts` runs `validateFeed` first and shows the errors *instead of* the
-console. Destinations are pure mappings, not validators: broadcasting from a
-broken feed would carry the same errors to every destination at once. Don't
+`main.ts` validates first and shows the errors *instead of* the console.
+Destinations are pure mappings, not validators: broadcasting from a broken
+feed would carry the same errors to every destination at once. Don't
 "improve" this into best-effort output with a warning.
 
+It validates with **`validateDocument`, not `validateFeed`** — this feed is
+one somebody else published, so it is judged against the version it declares.
+`validateFeed` is latest-only by design, and under it a perfectly valid 0.4
+feed came back invalid over its `specVersion` alone, so Broadcast refused to
+publish a healthy feed (#69). Being behind inside the support window is a
+**notice**, never a defect: `showNotices` puts those above `#main` and the
+feed still broadcasts. Never let a version notice take the early return the
+error path takes.
+
 ## Online-only events are not eligible for Google rich results — say so
 
 Google requires a physical location for event rich results ("Virtual
diff --git a/apps/publish/build.mjs b/apps/publish/build.mjs
index c3afdaa..9311121 100644
--- a/apps/publish/build.mjs
+++ b/apps/publish/build.mjs
@@ -10,13 +10,24 @@ const serve = process.argv.includes("--serve");
 // it here means the snippet can never drift from the deployed assets.
 const embedVersion = JSON.parse(readFileSync("../embed/package.json", "utf8")).version;
 
+// `splitting` with an outdir instead of a single outfile, the same shape and
+// for the same reason as apps/validator: validating a feed against the
+// version it declares (#69) means @opentechevents/validate can reach any
+// published version's compiled validators, and each one is a few hundred
+// kilobytes. They sit behind a dynamic import there, so esbuild gives each
+// its own chunk — without `splitting` they are all inlined and `main.js`
+// goes from 464 KB to 1.3 MB for versions this page will usually never meet.
 const options = {
   entryPoints: ["src/main.ts"],
   bundle: true,
+  splitting: true,
   format: "esm",
   platform: "browser",
   target: "es2022",
-  outfile: "dist/main.js",
+  outdir: "dist",
+  // The page loads ./main.js by name; only the shared chunks get hashes.
+  entryNames: "[name]",
+  chunkNames: "chunks/[name]-[hash]",
   sourcemap: true,
   minify: !serve,
   logLevel: "info",
diff --git a/apps/publish/src/main.ts b/apps/publish/src/main.ts
index 173e190..ae90a8f 100644
--- a/apps/publish/src/main.ts
+++ b/apps/publish/src/main.ts
@@ -1,5 +1,5 @@
 import { type OteFeed } from "@opentechevents/export-jsonld";
-import { validateFeed } from "@opentechevents/validate";
+import { validateDocument, type SpecVersionNotice } from "@opentechevents/validate";
 
 import { feedUrls, parseFeedSource, type FeedSource } from "./lib/feed-source.js";
 import { DEFAULT_EMBED_OPTIONS } from "./lib/site-snippets.js";
@@ -11,7 +11,7 @@ import {
 } from "./lib/store.js";
 import { renderAppBar, setFeedLabel, wireBrand, wireEventChip, wireTheme } from "./ui/app-bar.js";
 import type { AppContext, State } from "./ui/context.js";
-import { el } from "./ui/dom.js";
+import { el, link, sentence } from "./ui/dom.js";
 import { renderDestination, wireDestinationChrome } from "./ui/destination.js";
 import { wireEventPicker } from "./ui/event-picker.js";
 import { renderHome } from "./ui/home.js";
@@ -27,6 +27,26 @@ function showMessage(heading: string, body: string, isError: boolean): void {
   message.hidden = false;
 }
 
+/**
+ * Version notices, which are news rather than findings. The feed broadcasts
+ * either way, so this never returns early on the caller's behalf, and it
+ * renders above `#main` instead of in place of it.
+ *
+ * A notice keeps its `links` out of its sentence so a page can render them as
+ * links; this one does, rather than printing a bare URL mid-paragraph.
+ */
+function showNotices(notices: SpecVersionNotice[]): void {
+  if (notices.length === 0) return;
+  message.className = "panel";
+  message.replaceChildren(el("h2", undefined, "Worth knowing about this feed"));
+  for (const notice of notices) {
+    const parts: (string | Node)[] = [notice.message];
+    for (const target of notice.links) parts.push(" ", link(target.href, target.label));
+    message.append(sentence(...parts));
+  }
+  message.hidden = false;
+}
+
 /**
  * The whole navigation model: two views, one function that owns every piece of
  * chrome either of them needs. No router and no hash — the same shape
@@ -104,8 +124,14 @@ async function boot(): Promise<void> {
   // Every destination maps the feed's own fields onto someone else's format;
   // none of them validates. An invalid feed would be broadcast, errors and
   // all, to every destination at once — so it stops here.
-  const validation = validateFeed(json);
-  if (!validation.valid) {
+  //
+  // `validateDocument`, not `validateFeed`: this is a feed somebody else
+  // published, so it is judged against the version it declares. Against
+  // "latest" a valid 0.4 feed came back broken over its `specVersion` alone
+  // and Broadcast refused to publish it — being behind is a notice, never a
+  // defect (#69).
+  const report = await validateDocument(json, { kind: "feed" });
+  if (!report.valid) {
     message.className = "panel error";
     message.replaceChildren(
       el("h2", undefined, "This feed is not valid OTE"),
@@ -116,7 +142,7 @@ async function boot(): Promise<void> {
       ),
     );
     const list = el("ul");
-    for (const error of validation.errors) {
+    for (const error of report.errors) {
       const item = el("li");
       item.append(el("code", undefined, error.path), document.createTextNode(` — ${error.message}`));
       list.append(item);
@@ -126,6 +152,10 @@ async function boot(): Promise<void> {
     return;
   }
 
+  // Said, but not in the way of anything: a supported-but-older release is a
+  // legitimate choice, so this sits above the app instead of replacing it.
+  showNotices(report.notices);
+
   const feed = json as OteFeed;
   setFeedLabel(
     `${feed.title} · ${feed.events.length} event${feed.events.length === 1 ? "" : "s"}`,