diff --git a/docs/HANDOFF.md b/docs/HANDOFF.md
index 48e3ba9..c6dbec5 100644
--- a/docs/HANDOFF.md
+++ b/docs/HANDOFF.md
@@ -25,22 +25,30 @@ machine (or a new LLM) picks up the work cold.
 
 ## Current state of the code (2026-07-30)
 - **Phases 0–2 complete.** The daemon boots gRPC-only on loopback
-  `127.0.0.1:9420` behind a keyring bearer token, serving six services (System,
-  Accounts, Mail, Filters, Export, Audit), each behind the auth interceptor. The
+  `127.0.0.1:9420` behind a keyring bearer token, serving eight services (System,
+  Accounts, Mail, Filters, Calendar, Contacts, Export, Audit), each behind the
+  auth interceptor. The
   `IMAP → store → read → SMTP send` spine works end-to-end over gRPC via the
   `nuncio-cli` reference client, tested offline. `nuncio.v1` is published with a
   contract-stability golden.
-- **Phase 3 (feature completeness) is now COMPLETE — M1–M4 all merged to `dev`.**
+- **The feature surface (Phase 3 through M5) is now COMPLETE — M1–M5 all merged
+  to `dev`** (M1–M4 already promoted to `main`; M5 promotes next).
   Filter correctness (3.A), Calendar (M1: CalDAV + RRULE recurrence, API vertical),
   Contacts (M2: real CardDAV engine + API vertical), JMAP (M3: real client wired
-  into Mail sync), and Filters made live (M4: engine wired into sync with a
+  into Mail sync), Filters made live (M4: engine wired into sync with a
   fire-once guard, the `account`-field bug fixed, edit/export/import/logs and
-  `Filters.Triage` bulk rescan on the gRPC service) are all done.
-- **Next milestone: M5 — Mail lifecycle + incremental sync** (account
-  edit/delete/test-connection + persisted TLS mode, incremental IMAP sync with
-  progress + per-item FETCH timeout, explicit `SendMessage` account selection,
-  keyring rollback on failed `AddAccount`). Then M6 (security hardening), then
-  M7 (API freeze / client-readiness).
+  `Filters.Triage` bulk rescan on the gRPC service), and Mail lifecycle +
+  incremental sync (M5: account edit/delete/test-connection with persisted
+  `imap_tls_mode`/`smtp_tls_mode` driving the real IMAP/SMTP connection, a real
+  per-folder `{uidvalidity}:{uidnext}` incremental-sync checkpoint with a safe
+  full re-fetch on UIDVALIDITY change and a per-item FETCH timeout, explicit
+  `SendMessage` account selection, and keyring rollback on failed `AddAccount`)
+  are all done.
+- **Next milestone: M6 — Security & release hardening** (fail-closed
+  encryption, zeroized key material, WORM/ledger key-length validation,
+  non-loopback gRPC bind rejection + an auth-coverage canary, a fail-closed
+  updater on missing `SHA256SUMS`, real CIDR/DNS SSRF checks for webhooks,
+  inbound HTML email sanitization). Then M7 (API freeze / client-readiness).
 - Full detail and the path to a client-ready API: `docs/ROADMAP.md`.
 
 ## Branches & preserved WIP
@@ -94,7 +102,7 @@ GitHub milestones **M1–M7** mirror `docs/ROADMAP.md`. Each milestone holds
 `story`-labelled issues with a full, self-contained spec. Order: M1 → M7 (M1–M5
 independent-ish feature work; M6 security; M7 the client-readiness gate).
 
-**M1–M4 are DELIVERED — all stories merged to `dev`.** M5 is next.
+**M1–M5 are DELIVERED — all stories merged to `dev`.** M6 is next.
 
 **M1 — Finish Calendar (CalDAV)** · milestone #23 · **DONE**
 - #185 — Add Calendar API vertical (proto, daemon, CLI, E2E)  · **[PROTO]** · merged
@@ -113,13 +121,13 @@ independent-ish feature work; M6 security; M7 the client-readiness gate).
 - #192 — Move filter edit/export/import/logs onto the Filters gRPC service  · **[PROTO]** · merged
 - #193 — Re-expose bulk filter triage as a streaming Filters RPC  · **[PROTO]** *(depends on #190)* · merged
 
-**M5 — Mail lifecycle + incremental sync** · milestone #27 ← **next**
-- #194 — Account lifecycle over gRPC (edit/delete/test) + persist TLS mode  · **[PROTO]** *(prior art: `wip/unreviewed-account-tls-sync`, reference-not-trust)*
-- #195 — Incremental IMAP sync with progress reporting and per-item FETCH timeout
-- #196 — SendMessage selects an explicit account instead of the first configured  · **[PROTO]**
-- #197 — Roll back orphaned keyring secret when AddAccount fails to persist
+**M5 — Mail lifecycle + incremental sync** · milestone #27 · **DONE**
+- #194 — Account lifecycle over gRPC (edit/delete/test) + persist TLS mode  · **[PROTO]** *(prior art: `wip/unreviewed-account-tls-sync`, reference-not-trust)* · merged
+- #195 — Incremental IMAP sync with progress reporting and per-item FETCH timeout · merged
+- #196 — SendMessage selects an explicit account instead of the first configured  · **[PROTO]** · merged
+- #197 — Roll back orphaned keyring secret when AddAccount fails to persist · merged
 
-**M6 — Security & release hardening** · milestone #28
+**M6 — Security & release hardening** · milestone #28 ← **next**
 - #198 — Fail closed on encryption failure in `PayloadCipher::encrypt_text_at_rest`
 - #199 — Zeroize long-lived engine key material on drop
 - #200 — Validate WORM/ledger key length from the vault, fail closed on mismatch
@@ -145,7 +153,7 @@ independent-ish feature work; M6 security; M7 the client-readiness gate).
   those two issues if you consider that sensitive.
 - Decide the eventual fate of `wip/unreviewed-account-tls-sync` (review-and-adopt
   vs discard) once M5 lands a clean implementation.
-- Follow-ups filed during M1–M4 that are open but not blocking (not scheduled
+- Follow-ups filed during M1–M5 that are open but not blocking (not scheduled
   into a milestone yet): #216 (calendar windowing/predicate refinement), #219
   (contacts notes handling), #225 (`filter edit` silently re-enables a disabled
-  rule and resets `created_at`).
+  rule and resets `created_at`), #233 (M5 sync/SMTP robustness polish).
diff --git a/docs/ROADMAP.md b/docs/ROADMAP.md
index 1eed593..e3eac3d 100644
--- a/docs/ROADMAP.md
+++ b/docs/ROADMAP.md
@@ -53,8 +53,9 @@ offline. The legacy JSON-RPC IPC is removed. The `nuncio.v1` contract is
 published with a byte-deterministic `FileDescriptorSet` golden guarding it, plus
 external-codegen docs for Swift/C#/TypeScript.
 
-**Phase 3 — Feature completeness — is now COMPLETE**, via milestones M1–M4, all
-merged to `dev`:
+**The feature surface — Phase 3 through M5 — is now COMPLETE**, via milestones
+M1–M5, all merged to `dev` (M1–M4 are already promoted to `main`; M5 promotes
+next):
 
 - **3.A Filter correctness** — **done** (account scoping, `ON ACCOUNT`, non-ASCII
   offsets, `NOT IN`).
@@ -72,18 +73,30 @@ merged to `dev`:
   honestly rejected, filter edit/export/import/logs moved onto the `Filters`
   gRPC service, and a `Filters.Triage` server-streaming RPC does retroactive
   bulk rescan.
+- **Mail lifecycle & incremental sync** — **done** (M5). Account lifecycle
+  (`UpdateAccount`/`RemoveAccount`/`TestAccountConnection`) is real over gRPC,
+  with `imap_tls_mode`/`smtp_tls_mode` persisted and actually driving the real
+  IMAP (implicit/STARTTLS/plain) and SMTP connection. Sync is genuinely
+  incremental: a real per-folder `{uidvalidity}:{uidnext}` checkpoint narrows
+  the FETCH instead of re-fetching everything, a UIDVALIDITY change forces a
+  safe full re-fetch (no silent mail loss), a per-item FETCH timeout replaces
+  the indefinite hang, and a `SyncProgress` event is emitted. `SendMessage`
+  takes an explicit `account_id` (honest `AccountNotFound`, no silent
+  wrong-account fallback), and `AddAccount` rolls back an orphaned keyring
+  secret if persistence fails.
 
-**Next up: M5 — Mail lifecycle & incremental sync** (account edit/delete/test +
-persisted TLS mode, incremental IMAP sync with progress + per-item FETCH
-timeout, explicit `SendMessage` account selection, keyring rollback on failed
-`AddAccount`). Then M6 (security hardening), then M7 (API freeze / client
-readiness).
+**Next up: M6 — Security & release hardening** (fail-closed encryption,
+zeroized key material, WORM/ledger key-length validation, a rejection of
+non-loopback gRPC binds plus an auth-coverage canary, a fail-closed updater on
+missing `SHA256SUMS`, real CIDR/DNS SSRF checks for webhooks, inbound HTML
+email sanitization). Then M7 (API freeze / client-readiness).
 
-A handful of follow-ups were filed during M1–M4 and remain open, tracked as
-their own backlog items rather than blocking M1–M4's completion: calendar
-windowing/predicate refinement (#216), contacts notes handling (#219), and a
+A handful of follow-ups were filed during M1–M5 and remain open, tracked as
+their own backlog items rather than blocking completion: calendar
+windowing/predicate refinement (#216), contacts notes handling (#219), a
 `filter edit` bug where re-saving a rule silently re-enables it and resets
-`created_at` (#225).
+`created_at` (#225), and further mail sync/SMTP robustness polish identified
+during M5 (#233).
 
 **Explicitly deferred** (out of scope until the backend is client-ready and each
 is re-justified as a genuine engine capability): OpenPGP/S-MIME E2EE (#79),
diff --git a/docs/roadmap/index.html b/docs/roadmap/index.html
index c09c6fb..524df65 100644
--- a/docs/roadmap/index.html
+++ b/docs/roadmap/index.html
@@ -76,7 +76,7 @@
   /* milestone rail */
   .miles{position:relative;margin-top:8px}
   .miles::before{content:"";position:absolute;left:19px;top:12px;bottom:34px;width:2px;
-    background:linear-gradient(var(--done),var(--done) 57%,var(--prog) 57%,var(--prog) 71%,var(--line) 71%);border-radius:2px}
+    background:linear-gradient(var(--done),var(--done) 71%,var(--prog) 71%,var(--prog) 86%,var(--line) 86%);border-radius:2px}
   @media (max-width:640px){.miles::before{display:none}}
   .m{position:relative;padding-left:52px;margin-bottom:16px}
   @media (max-width:640px){.m{padding-left:0}}
@@ -135,14 +135,15 @@
 
   <h2>Where we are · 2026-07-30</h2>
   <div class="band">
-    <h3>Phases 0–2 complete, Phase 3 feature completeness done — M1–M4 all merged</h3>
+    <h3>Phases 0–2 complete, feature surface (Phase 3–M5) done — M1–M5 all merged</h3>
     <p>The daemon boots gRPC-only on loopback <span class="chip">127.0.0.1:9420</span> behind a keyring-minted
       bearer token. <code>IMAP → store → read → SMTP send</code> runs end-to-end over gRPC, driven by the
       <span class="chip">nuncio-cli</span> reference client, tested fully offline. The legacy JSON-RPC IPC is gone,
       and <span class="chip">nuncio.v1</span> is published with a byte-deterministic contract-stability golden.
-      Milestones M1–M4 are now complete on <span class="chip">dev</span>: Calendar, Contacts, JMAP, and live
-      Filters are all real, wired, and API-complete. <b style="color:var(--ink)">Next up: M5</b> (mail lifecycle
-      &amp; incremental sync).</p>
+      Milestones M1–M5 are now complete on <span class="chip">dev</span> (M1–M4 already promoted to
+      <span class="chip">main</span>): Calendar, Contacts, JMAP, live Filters, and mail lifecycle + incremental
+      sync are all real, wired, and API-complete. <b style="color:var(--ink)">Next up: M6</b> (security &amp;
+      release hardening).</p>
     <div class="chips">
       <span class="chip svc">System</span><span class="chip svc">Accounts</span><span class="chip svc">Mail</span>
       <span class="chip svc">Filters</span><span class="chip svc">Calendar</span><span class="chip svc">Contacts</span>
@@ -158,6 +159,7 @@
       <span class="donetag">M2 · Contacts (CardDAV)</span>
       <span class="donetag">M3 · JMAP</span>
       <span class="donetag">M4 · Filters made live</span>
+      <span class="donetag">M5 · Mail lifecycle + incremental sync</span>
     </div>
   </div>
 
@@ -226,27 +228,31 @@
       </div>
     </div>
 
-    <div class="m prog">
+    <div class="m done">
       <div class="node">M5</div>
       <div class="card">
         <div class="chead">
           <h3 class="ctitle"><span class="code">M5</span>Mail lifecycle + incremental sync</h3>
-          <span class="stat prog">Next</span>
+          <span class="stat done">Done</span>
         </div>
-        <p class="cbody">Round out real account management: edit / delete / test-connection with TLS modes
-          (implicit / STARTTLS / plain) actually wired; explicit send-account selection; and <b>incremental sync</b>
-          (honor <code>since_state</code> instead of re-fetching the whole mailbox every time) with progress and stall timeouts.</p>
+        <p class="cbody">Account lifecycle (edit / delete / test-connection) is real over gRPC, with TLS modes
+          (implicit / STARTTLS / plain) persisted and actually driving the IMAP/SMTP connection. Sync is now
+          genuinely incremental via a per-folder <code>{uidvalidity}:{uidnext}</code> checkpoint (a UIDVALIDITY
+          change forces a safe full re-fetch — no silent mail loss), with a per-item FETCH timeout and
+          <code>SyncProgress</code> events. <code>SendMessage</code> takes an explicit account id (honest
+          <code>AccountNotFound</code>, no silent wrong-account fallback), and a failed <code>AddAccount</code>
+          rolls back its orphaned keyring secret.</p>
         <div class="exit"><b>Exit:</b> full account lifecycle + incremental sync, offline-E2E-proven, no fabricated IMAP fallbacks.</div>
-        <div class="issues"><a class="iss">#170</a><a class="iss">#169</a><a class="iss">#182</a><a class="iss">#183</a><a class="iss">#184</a></div>
+        <div class="issues"><a class="iss">#170</a><a class="iss">#169</a><a class="iss">#182</a><a class="iss">#183</a><a class="iss">#184</a><span class="iss">done — #194–#197 merged</span></div>
       </div>
     </div>
 
-    <div class="m plan">
+    <div class="m prog">
       <div class="node">M6</div>
       <div class="card">
         <div class="chead">
           <h3 class="ctitle"><span class="code">M6</span>Security &amp; release hardening</h3>
-          <span class="stat plan">Planned</span>
+          <span class="stat prog">Next</span>
         </div>
         <p class="cbody">Fail-<i>closed</i> everywhere: fix the silent empty-ciphertext data-loss path; a
           signature-verifying updater that refuses to apply without checksums; zeroize key material; validate vault