diff --git a/server/src/systemNotices/registry.ts b/server/src/systemNotices/registry.ts
index faf2f8198..20e901348 100644
--- a/server/src/systemNotices/registry.ts
+++ b/server/src/systemNotices/registry.ts
@@ -36,10 +36,13 @@ export const RETIRED_NOTICE_IDS = [
 export const SYSTEM_NOTICES: SystemNotice[] = [
   // ── 4.0.0 release — what shipped, and a note from the maintainer ────────────
   // Carries `release`, so it renders as the two-column release modal rather than
-  // the generic notice body. Shown once, not per-version: the copy is about this
-  // release. The next one gets its own entry with its own id.
+  // the generic notice body. 4.0.0 was big enough that the whole 4.x line should
+  // carry it, so `recurring: 'per-version'` brings it back on each upgrade inside
+  // the window rather than the default one-time dismissal, which retired it for
+  // everyone who closed it once on 4.0.0. A 5.x release gets its own entry.
   {
     id: 'release-4-0-0',
+    recurring: 'per-version',
     display: 'modal',
     severity: 'info',
     titleKey: 'system_notice.release_400.headline',
diff --git a/server/tests/unit/systemNotices/registry.test.ts b/server/tests/unit/systemNotices/registry.test.ts
index 0d7a4d6c7..aab20dc0e 100644
--- a/server/tests/unit/systemNotices/registry.test.ts
+++ b/server/tests/unit/systemNotices/registry.test.ts
@@ -82,6 +82,14 @@ describe('registry integrity', () => {
     expect(isNoticeVersionActive(release!, '5.0.0')).toBe(false);
   });
 
+  it('the 4.0.0 release notice comes back on each upgrade inside that line', () => {
+    const release = SYSTEM_NOTICES.find(n => n.id === 'release-4-0-0')!;
+    // The version window above is only half of "covers the whole 4.x line". Without
+    // this, the default one-time dismissal retired the notice for everyone who
+    // closed it on 4.0.0, so none of them saw it again on 4.1, 4.2 or later.
+    expect(release.recurring).toBe('per-version');
+  });
+
   it('the thank-you notice hands over to the release modal at 4.0.0', () => {
     const thankYou = SYSTEM_NOTICES.find(n => n.id === 'thank-you-support');
     expect(thankYou).toBeDefined();