diff --git a/docs/PRD.md b/docs/PRD.md
index 0883ff0..2941c41 100644
--- a/docs/PRD.md
+++ b/docs/PRD.md
@@ -462,6 +462,11 @@ counted, in the same words the empty list uses — *the games you have switched
 column beside it is owed to every source we read and is not scoped; nor is the "last refreshed" line,
 which reports the feed and feeds the bug form.
 
+**The staleness notice differentiates crawler checks from site updates.** If our crawler successfully
+checked the wiki recently (e.g. confirming HTTP 304) but the site's content has not changed in over
+two days, the notice explicitly distinguishes the two: "data pulled X ago, site updated Y ago", with
+an expandable breakdown detailing each source's check and content update times.
+
 **F15 — Light mode, with dark still the default.**
 The app is a lit instrument panel and that is what it should be on first sight, but it is also read
 on a train in daylight and by people who find a dark UI harder rather than moodier. A public fork
diff --git a/src/client/components/Colophon.tsx b/src/client/components/Colophon.tsx
index f5db915..0e31dc2 100644
--- a/src/client/components/Colophon.tsx
+++ b/src/client/components/Colophon.tsx
@@ -1,6 +1,6 @@
 import { useGameMeta } from "../state/gameMeta.tsx";
 import type { LaneId } from "../../shared/custom.ts";
-import { freshness, type SourceHealth } from "../../shared/feed.ts";
+import { freshness, STALE_AFTER_MS, type SourceHealth, type StaleGame } from "../../shared/feed.ts";
 import { formatAbsolute, formatRemaining } from "../../shared/time.ts";
 
 export const REPO_URL = "https://github.com/StereotypicalCat/gacha-event-tracker";
@@ -124,6 +124,29 @@ function siteFor(url: string): { name: string; url: string } {
   }
 }
 
+function formatStaleAge(s: StaleGame, now: number): string {
+  if (s.lastSuccessAt === null && s.contentChangedAt === null) {
+    return " (never)";
+  }
+
+  const contentDate = s.contentChangedAt ?? s.lastSuccessAt;
+  const contentAgo = contentDate
+    ? `${formatRemaining(now - Date.parse(contentDate))} ago`
+    : null;
+
+  // Differentiate blame when crawler confirmed the source recently (<= STALE_AFTER_MS)
+  // but the site content has not changed in over 2 days.
+  if (s.lastConfirmedAt !== null) {
+    const confirmedAge = now - Date.parse(s.lastConfirmedAt);
+    if (confirmedAge <= STALE_AFTER_MS) {
+      const confirmedAgo = `${formatRemaining(confirmedAge)} ago`;
+      return ` (data pulled ${confirmedAgo}, site updated ${contentAgo ?? "unknown"})`;
+    }
+  }
+
+  return contentAgo ? ` (${contentAgo})` : " (never)";
+}
+
 /**
  * Credit, disclaimer, and where the code lives.
  *
@@ -253,9 +276,7 @@ export function Colophon({
                     <span key={s.game}>
                       {i > 0 && (i === shown.length - 1 && shownStale.length <= STALE_NAMES ? " and " : ", ")}
                       {gameMeta(s.game).name}
-                      {s.lastSuccessAt === null
-                        ? " (never)"
-                        : ` (${formatRemaining(now - Date.parse(s.lastSuccessAt))} ago)`}
+                      {formatStaleAge(s, now)}
                     </span>
                   ))}
                   {shownStale.length > STALE_NAMES &&
@@ -267,6 +288,57 @@ export function Colophon({
               )}
             </p>
           )}
+
+          {shownStale.some((s) => s.sources && s.sources.length > 0) && (
+            <details className="mt-2 text-faint">
+              <summary className="cursor-pointer hover:text-muted focus-visible:outline-none">
+                Source breakdown
+              </summary>
+              <ul className="mt-1.5 space-y-1 border-l border-hairline pl-3">
+                {shownStale.flatMap((g) =>
+                  g.sources.map((src) => {
+                    const site = siteFor(src.url);
+                    const confirmed = src.lastConfirmedAt
+                      ? `${formatRemaining(now - Date.parse(src.lastConfirmedAt))} ago`
+                      : "never";
+                    const updated = src.contentChangedAt
+                      ? `${formatRemaining(now - Date.parse(src.contentChangedAt))} ago`
+                      : src.lastSuccessAt
+                        ? `${formatRemaining(now - Date.parse(src.lastSuccessAt))} ago`
+                        : "never";
+                    const isPullRecent =
+                      src.lastConfirmedAt !== null &&
+                      now - Date.parse(src.lastConfirmedAt) <= STALE_AFTER_MS;
+                    const isContentStale =
+                      src.contentChangedAt === null ||
+                      now - Date.parse(src.contentChangedAt) > STALE_AFTER_MS;
+                    const diagnosis =
+                      isPullRecent && isContentStale
+                        ? "site has no new updates"
+                        : !isPullRecent
+                          ? "pull overdue"
+                          : "up to date";
+
+                    return (
+                      <li key={src.sourceId}>
+                        <span className="text-muted">{gameMeta(g.game).name}</span>
+                        {" — "}
+                        <a
+                          href={src.url}
+                          target="_blank"
+                          rel="noreferrer noopener"
+                          className={LINK}
+                        >
+                          {site.name}
+                        </a>
+                        {`: pulled ${confirmed}, site updated ${updated} (${diagnosis})`}
+                      </li>
+                    );
+                  }),
+                )}
+              </ul>
+            </details>
+          )}
         </div>
 
         <div className="mt-5 lg:mt-0">
diff --git a/test/custom-ui.test.tsx b/test/custom-ui.test.tsx
index 500af49..875dc04 100644
--- a/test/custom-ui.test.tsx
+++ b/test/custom-ui.test.tsx
@@ -237,6 +237,8 @@ describe("Colophon freshness notice (PRD F7)", () => {
     game: "genshin" as const,
     url: "https://game8.co/games/Genshin-Impact/archives/301601",
     lastSuccessAt: new Date(NOW - 3 * HOUR).toISOString(),
+    lastConfirmedAt: null,
+    contentChangedAt: null,
     eventCount: 9,
 
     parsedCount: 9,
@@ -277,6 +279,31 @@ describe("Colophon freshness notice (PRD F7)", () => {
     expect(html).toContain("3h 0m ago");
   });
 
+  test("differentiates blame when data was pulled recently but site has not changed", () => {
+    const html = renderToStaticMarkup(
+      <Colophon
+        sources={[
+          fresh,
+          {
+            ...fresh,
+            sourceId: "endfield-wikigg-events",
+            game: "endfield",
+            url: "https://endfield.wiki.gg/wiki/Event",
+            lastSuccessAt: new Date(NOW - 57 * HOUR).toISOString(),
+            lastConfirmedAt: new Date(NOW - 11 * HOUR).toISOString(),
+            contentChangedAt: new Date(NOW - 57 * HOUR).toISOString(),
+          },
+        ]}
+        now={NOW}
+      />,
+    );
+    expect(html).toContain("Arknights: Endfield");
+    expect(html).toContain("data pulled 11h 0m ago, site updated 2d 9h ago");
+    expect(html).toContain("Source breakdown");
+    expect(html).toContain("wiki.gg");
+    expect(html).toContain("site has no new updates");
+  });
+
   test("summarises instead of listing when every game is behind", () => {
     // What a refresh that stopped running looks like. Ten names each repeating
     // the same age is less readable than the count this replaced.
diff --git a/test/issue-templates.test.tsx b/test/issue-templates.test.tsx
index 67a12d8..1e46197 100644
--- a/test/issue-templates.test.tsx
+++ b/test/issue-templates.test.tsx
@@ -165,6 +165,8 @@ describe("the app's links into them", () => {
             game: "genshin",
             url: "https://game8.co/games/Genshin-Impact/archives/301601",
             lastSuccessAt: new Date(NOW - 3 * 60 * 60 * 1000).toISOString(),
+            lastConfirmedAt: null,
+            contentChangedAt: new Date(NOW - 3 * 60 * 60 * 1000).toISOString(),
             eventCount: 9,
 
             parsedCount: 9,