diff --git a/CHANGELOG.md b/CHANGELOG.md
index de014156..142934e1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,10 @@
 
 ## [Unreleased]
 
+### Removed
+- **Reverted the manual per-session status labels (Todo / In Progress / Done).** The feature added in v0.51.284 (#3570) stored the chosen status only in browser `localStorage`, keyed by session id, with no server-side backing — so labels silently did not persist across browsers or devices (a user who labeled sessions on one machine saw none of them after switching to a laptop). It also rendered the three statuses as flat top-level entries in the session context menu alongside Copy/Rename/Pin/etc., which crowded the root menu. Removed entirely for now (JS state + cycle logic, context-menu entries, sidebar badge render, CSS, and all locale strings); the feature can be reintroduced later with proper server-side persistence and a less intrusive menu treatment. (reverts #3570)
+
+
 ## [v0.51.294] — 2026-06-06 — Release JJ (stage-3401 — live-to-final assistant reply redesign)
 
 ### Changed
diff --git a/api/routes.py b/api/routes.py
index deac7e82..925247e6 100644
--- a/api/routes.py
+++ b/api/routes.py
@@ -1955,6 +1955,7 @@ def _resolve_compatible_session_model_state(
     *,
     profile_provider: str | None = None,
     profile_default_model: str | None = None,
+    explicit_model_pick: bool = False,
 ) -> tuple[str, str | None, bool]:
     """Return (effective_model, effective_provider, model_was_normalized).
 
@@ -2020,6 +2021,9 @@ def _resolve_compatible_session_model_state(
                 break
 
         if model_family and model_family != _profile_provider_normalized:
+            if explicit_model_pick:
+                # User explicitly chose a cross-family model; honor it (#3737)
+                return model, profile_provider, False
             _target = _profile_default or default_model
             return _target, profile_provider, True
 
@@ -2117,6 +2121,9 @@ def _resolve_compatible_session_model_state(
 
     slash = model.find("/")
     if slash < 0:
+        if explicit_model_pick:
+            # User explicitly chose this model; don't second-guess (#3737)
+            return model, requested_provider, False
         model_lower = model.lower()
         for bare_prefix in ("gpt", "claude", "gemini"):
             if model_lower.startswith(bare_prefix):
@@ -11408,12 +11415,14 @@ def _handle_chat_start(handler, body, diag=None):
             else getattr(s, "model_provider", None)
         )
         _pp_provider, _pp_default = _read_profile_model_config(s, requested_provider)
+        explicit_model_pick = bool(body.get("explicit_model_pick"))
         diag.stage("resolve_model_provider") if diag else None
         model, model_provider, normalized_model = _resolve_compatible_session_model_state(
             requested_model,
             requested_provider,
             profile_provider=_pp_provider,
             profile_default_model=_pp_default,
+            explicit_model_pick=explicit_model_pick,
         )
         from api.runtime_adapter import (
             LegacyJournalRuntimeAdapter,
diff --git a/static/boot.js b/static/boot.js
index 01ec91d4..497e6cd6 100644
--- a/static/boot.js
+++ b/static/boot.js
@@ -1202,12 +1202,11 @@ $('modelSelect').onchange=async()=>{
     model:modelState.model,
     model_provider:modelState.model_provider||null,
   })});
-  if(typeof _readPendingSessionModel==='function'&&typeof _clearPendingSessionModel==='function'){
-    const pending=_readPendingSessionModel(S.session.session_id);
-    if(!pending||(pending.model===modelState.model&&String(pending.model_provider||'')===String(modelState.model_provider||''))){
-      _clearPendingSessionModel(S.session.session_id);
-    }
-  }
+  // NOTE: do NOT clear the pending explicit-pick marker here. It must survive until
+  // the NEXT send() consumes it, otherwise the normal "pick → session-update → send"
+  // flow loses the explicit-pick signal before /api/chat/start runs and the server
+  // re-reverts a cross-family pick (the #3737 bug, Codex catch). send() clears it
+  // after reading a matching pending pick. (#3739/#3737)
   _applySessionContextMetadataUpdate(data);
   // Warn if selected model belongs to a different provider than what Hermes is configured for
   if(typeof _checkProviderMismatch==='function'){
diff --git a/static/i18n.js b/static/i18n.js
index 9834848e..e0a2631a 100644
--- a/static/i18n.js
+++ b/static/i18n.js
@@ -670,10 +670,6 @@ const LOCALES = {
     kanban_status_running: 'Running',
     kanban_status_blocked: 'Blocked',
     kanban_status_done: 'Done',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_comments_count: 'Comments ({0})',
     kanban_events_count: 'Events ({0})',
     kanban_links: 'Links',
@@ -2014,10 +2010,6 @@ const LOCALES = {
     kanban_status_running: 'In esecuzione',
     kanban_status_blocked: 'Bloccato',
     kanban_status_done: 'Completato',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_comments_count: 'Commenti ({0})',
     kanban_events_count: 'Eventi ({0})',
     kanban_links: 'Link',
@@ -3350,10 +3342,6 @@ const LOCALES = {
     kanban_status_running: '実行中',
     kanban_status_blocked: 'ブロック中',
     kanban_status_done: '完了',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_status_original_hint: '実際のステータス: {0}。このダイアログはトリアージ/ToDo/準備完了の編集のみ対応しています。',
     kanban_comments_count: 'コメント ({0})',
     kanban_events_count: 'イベント ({0})',
@@ -4478,10 +4466,6 @@ const LOCALES = {
     kanban_status_running: 'Running',
     kanban_status_blocked: 'Blocked',
     kanban_status_done: 'Done',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_status_original_hint: 'Actual status: {0}. This dialog only supports Triage/Todo/Ready edits.',
     kanban_comments_count: 'Comments ({0})',
     kanban_events_count: 'Events ({0})',
@@ -5751,10 +5735,6 @@ const LOCALES = {
     kanban_status_running: 'Running',
     kanban_status_blocked: 'Blocked',
     kanban_status_done: 'Done',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_status_original_hint: 'Actual status: {0}. This dialog only supports Triage/Todo/Ready edits.',
     kanban_comments_count: 'Comments ({0})',
     kanban_events_count: 'Events ({0})',
@@ -7008,10 +6988,6 @@ const LOCALES = {
     kanban_status_running: 'Running',
     kanban_status_blocked: 'Blocked',
     kanban_status_done: 'Done',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_status_original_hint: 'Actual status: {0}. This dialog only supports Triage/Todo/Ready edits.',
     kanban_comments_count: 'Comments ({0})',
     kanban_events_count: 'Events ({0})',
@@ -8308,10 +8284,6 @@ const LOCALES = {
     kanban_status_running: '进行中',
     kanban_status_blocked: '阻塞',
     kanban_status_done: '完成',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_status_original_hint: '实际状态：{0}。此对话框仅支持编辑 Triage/Todo/Ready。',
     kanban_comments_count: '评论 ({0})',
     kanban_events_count: '事件 ({0})',
@@ -9779,10 +9751,6 @@ const LOCALES = {
     kanban_status_running: '執行中',
     kanban_status_blocked: '已封鎖',
     kanban_status_done: '完成',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_comments_count: '留言 ({0})',
     kanban_events_count: '事件 ({0})',
     kanban_links: '連結',
@@ -10999,10 +10967,6 @@ const LOCALES = {
     kanban_status_running: 'Running',
     kanban_status_blocked: 'Blocked',
     kanban_status_done: 'Done',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_status_original_hint: 'Actual status: {0}. This dialog only supports Triage/Todo/Ready edits.',
     kanban_comments_count: 'Comments ({0})',
     kanban_events_count: 'Events ({0})',
@@ -12235,10 +12199,6 @@ const LOCALES = {
     kanban_status_running: 'Running',
     kanban_status_blocked: 'Blocked',
     kanban_status_done: 'Done',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_status_original_hint: 'Actual status: {0}. This dialog only supports Triage/Todo/Ready edits.',
     kanban_comments_count: 'Comments ({0})',
     kanban_events_count: 'Events ({0})',
@@ -13495,10 +13455,6 @@ const LOCALES = {
     kanban_status_running: 'En cours d\'exécution',
     kanban_status_blocked: 'Bloqué',
     kanban_status_done: 'Fait',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_comments_count: 'Commentaires ({0})',
     kanban_events_count: 'Événements ({0})',
     kanban_links: 'Links',
@@ -14843,10 +14799,6 @@ const LOCALES = {
     kanban_status_running: 'Koşma',
     kanban_status_blocked: 'Engellendi',
     kanban_status_done: 'Tamamlamak',
-    session_status_todo: 'Todo',
-    session_status_in_progress: 'In Progress',
-    session_status_done: 'Done',
-    session_status_click_to_change: 'Click to cycle status',
     kanban_status_original_hint: 'Gerçek durum: {0}. Bu iletişim kutusu yalnızca Triyaj/Yapılacak/Hazır düzenlemelerini destekler.',
     kanban_comments_count: 'Yorumlar ({0})',
     kanban_events_count: 'Etkinlikler ({0})',
diff --git a/static/messages.js b/static/messages.js
index 520fd126..0c481b90 100644
--- a/static/messages.js
+++ b/static/messages.js
@@ -655,6 +655,18 @@ async function send(){
   let streamId;
   try{
     const _modelState=_chatPayloadModelState();
+    const _pendingPick=(typeof _readPendingSessionModel==='function')
+      ? _readPendingSessionModel(activeSid)
+      : null;
+    const _explicitPick=_pendingPick
+      && _pendingPick.model===_modelState.model
+      && String(_pendingPick.model_provider||'')===String(_modelState.model_provider||'');
+    // Consume the pending explicit-pick marker for THIS send only. The marker is
+    // recorded on modelSelect.onchange and intentionally kept (not cleared on
+    // session-update) so it survives the normal pick→update→send flow; clear it here
+    // once read so a later send of an unchanged dropdown isn't treated as an explicit
+    // pick. (#3739/#3737, Codex catch)
+    if(_explicitPick && typeof _clearPendingSessionModel==='function') _clearPendingSessionModel(activeSid);
     const startData=await api('/api/chat/start',{method:'POST',body:JSON.stringify({
       session_id:activeSid,message:msgText,
       // S.session.model remains authoritative; the helper only resolves a
@@ -662,12 +674,17 @@ async function send(){
       model:_modelState.model,workspace:S.session.workspace,
       model_provider:_modelState.model_provider,
       profile:S.activeProfile||S.session.profile||'default',
+      explicit_model_pick:_explicitPick||undefined,
       attachments:uploaded.length?uploaded:undefined
     })});
 
     if(startData.title) applySessionTitleUpdate(activeSid, startData.title, {provisionalText:displayText.slice(0,64), rememberProvisional:true});
 
     if(startData.effective_model && S.session){
+      const _sentModel=_modelState.model;
+      if(_explicitPick && _sentModel && startData.effective_model!==_sentModel && typeof showToast==='function'){
+        showToast('Model '+_sentModel+' changed to '+startData.effective_model+' — profile provider mismatch', 5000);
+      }
       S.session.model=startData.effective_model;
       S.session.model_provider=startData.effective_model_provider||S.session.model_provider||null;
       localStorage.setItem('hermes-webui-model', startData.effective_model);
diff --git a/static/sessions.js b/static/sessions.js
index d202cc3d..cff71d20 100644
--- a/static/sessions.js
+++ b/static/sessions.js
@@ -170,7 +170,6 @@ function _clearComposerDraft(sid) {
 const SESSION_VIEWED_COUNTS_KEY = 'hermes-session-viewed-counts';
 const SESSION_COMPLETION_UNREAD_KEY = 'hermes-session-completion-unread';
 const SESSION_OBSERVED_STREAMING_KEY = 'hermes-session-observed-streaming';
-const SESSION_MANUAL_STATUS_KEY = 'hermes-session-manual-status';
 let _sessionViewedCounts = null;
 let _sessionCompletionUnread = null;
 let _sessionObservedStreaming = null;
@@ -354,43 +353,6 @@ function _isServerIdleSessionRow(s) {
   return Boolean(s && s.session_id && !s.is_streaming && !s.active_stream_id && !s.pending_user_message);
 }
 
-// ── Manual session status (Todo / In Progress / Done) ─────────────────────
-const _SESSION_STATUS_VALUES = ['todo', 'in-progress', 'done'];
-
-function _getSessionManualStatuses() {
-  try {
-    const parsed = JSON.parse(localStorage.getItem(SESSION_MANUAL_STATUS_KEY) || '{}');
-    return parsed && typeof parsed === 'object' && !Array.isArray(parsed) ? parsed : {};
-  } catch (_e) { return {}; }
-}
-
-function getSessionManualStatus(sid) {
-  if (!sid) return null;
-  const val = _getSessionManualStatuses()[sid];
-  return _SESSION_STATUS_VALUES.includes(val) ? val : null;
-}
-
-function setSessionManualStatus(sid, status) {
-  if (!sid) return;
-  const map = _getSessionManualStatuses();
-  if (status && _SESSION_STATUS_VALUES.includes(status)) {
-    map[sid] = status;
-  } else {
-    delete map[sid];
-  }
-  try { localStorage.setItem(SESSION_MANUAL_STATUS_KEY, JSON.stringify(map)); } catch (_e) {}
-  renderSessionListFromCache();
-}
-
-function _cycleSessionManualStatus(session) {
-  const current = getSessionManualStatus(session.session_id);
-  const idx = _SESSION_STATUS_VALUES.indexOf(current);
-  const next = idx === -1 ? _SESSION_STATUS_VALUES[0]
-    : idx === _SESSION_STATUS_VALUES.length - 1 ? null
-    : _SESSION_STATUS_VALUES[idx + 1];
-  setSessionManualStatus(session.session_id, next);
-}
-
 function _reconcileActiveSessionIdleStateFromList(serverRows) {
   if (!S || !S.session || !S.session.session_id) return false;
   if (typeof _sendInProgress !== 'undefined' && _sendInProgress) return false;
@@ -3028,22 +2990,6 @@ function _openSessionActionMenu(session, anchorEl){
       }
     ));
   }
-  // Manual status picker (before danger actions)
-  if (!isExternalSession) {
-    const currentStatus = getSessionManualStatus(session.session_id);
-    for (const status of _SESSION_STATUS_VALUES) {
-      menu.appendChild(_buildSessionAction(
-        t('session_status_' + status.replace(/-/g,'_')) || status,
-        '',
-        '',
-        () => {
-          closeSessionActionMenu();
-          setSessionManualStatus(session.session_id, currentStatus === status ? null : status);
-        },
-        currentStatus === status ? 'is-active' : ''
-      ));
-    }
-  }
   if(!isExternalSession){
     if(session.worktree_path){
       menu.appendChild(_buildSessionAction(
@@ -5026,15 +4972,6 @@ function renderSessionListFromCache(){
         titleRow.appendChild(dot);
       }
     }
-    const manualStatus = getSessionManualStatus(s.session_id);
-    if (manualStatus) {
-      const statusBadge = document.createElement('span');
-      statusBadge.className = 'session-manual-status session-manual-status--' + manualStatus;
-      statusBadge.textContent = t('session_status_' + manualStatus.replace(/-/g,'_')) || manualStatus;
-      statusBadge.title = t('session_status_click_to_change') || 'Click to change status';
-      statusBadge.onclick = (e) => { e.stopPropagation(); _cycleSessionManualStatus(s); };
-      titleRow.appendChild(statusBadge);
-    }
     const density=(window._sidebarDensity==='detailed'?'detailed':'compact');
     const showLineageMetadata=density==='detailed';
     const lineageKey=_sidebarLineageKeyForRow(s);
diff --git a/static/style.css b/static/style.css
index 6cd765ee..dbea5a93 100644
--- a/static/style.css
+++ b/static/style.css
@@ -4109,13 +4109,6 @@ main.main > #mainPlugin{display:none;}
    the row's gap:6px handles spacing, no margin/vertical-align needed. */
 .session-project-dot{width:6px;height:6px;border-radius:50%;flex-shrink:0;display:inline-block;}
 
-/* Manual session status badge */
-.session-manual-status{display:inline-flex;align-items:center;padding:1px 6px;border-radius:999px;font-size:9px;font-weight:700;letter-spacing:.04em;text-transform:uppercase;flex-shrink:0;cursor:pointer;line-height:1.6;border:1px solid transparent;transition:opacity .12s;}
-.session-manual-status:hover{opacity:.75;}
-.session-manual-status--todo{background:rgba(99,179,237,.18);border-color:rgba(99,179,237,.35);color:#63b3ed;}
-.session-manual-status--in-progress{background:rgba(246,173,85,.18);border-color:rgba(246,173,85,.35);color:#f6ad55;}
-.session-manual-status--done{background:rgba(72,187,120,.18);border-color:rgba(72,187,120,.35);color:#48bb78;}
-
 /* ── Code copy button ── */
 .code-copy-btn{background:var(--hover-bg);border:1px solid var(--border2);border-radius:4px;color:var(--muted);font-size:11px;cursor:pointer;padding:2px 6px;transition:all .15s;line-height:1.3;}
 .code-copy-btn:hover{background:rgba(255,255,255,.12);color:var(--text);}
diff --git a/tests/test_issue3737_explicit_pick_client_wiring.py b/tests/test_issue3737_explicit_pick_client_wiring.py
new file mode 100644
index 00000000..9d445684
--- /dev/null
+++ b/tests/test_issue3737_explicit_pick_client_wiring.py
@@ -0,0 +1,75 @@
+"""Regression guard for the #3737 explicit-pick CLIENT clear-timing fix (PR #3739 + Codex catch).
+
+The server-side resolver coverage lives in test_provider_mismatch.py
+(test_explicit_pick_survives_profile_family_mismatch / _false_allows_normalization).
+
+This file locks the CLIENT-side wiring that makes the flag actually engage in the
+normal flow. Codex found that boot.js modelSelect.onchange cleared the pending
+explicit-pick marker right after /api/session/update, so by the time send() ran the
+marker was gone, _explicitPick was false, and the server reverted the cross-family
+pick anyway — the flag only worked in a rare race. The fix:
+
+  * onchange RECORDS the pick (_rememberPendingSessionModel) and must NOT clear it;
+  * send() consumes it (reads, then _clearPendingSessionModel) for that send only.
+
+These are static source-structure assertions (the flow is DOM/network-driven and
+exercised live); they keep the clear-timing from silently regressing.
+"""
+from __future__ import annotations
+
+import re
+from pathlib import Path
+
+REPO = Path(__file__).resolve().parent.parent
+BOOT_JS = (REPO / "static" / "boot.js").read_text(encoding="utf-8")
+MESSAGES_JS = (REPO / "static" / "messages.js").read_text(encoding="utf-8")
+
+
+def _model_onchange_region() -> str:
+    """The modelSelect.onchange handler body where the pending pick is recorded and
+    the /api/session/update round-trip happens."""
+    idx = BOOT_JS.find("_rememberPendingSessionModel")
+    assert idx != -1, "_rememberPendingSessionModel call not found in boot.js"
+    # Window from the remember call through the session-update POST + its aftermath.
+    return BOOT_JS[idx: idx + 1200]
+
+
+def test_onchange_records_pending_pick():
+    region = _model_onchange_region()
+    assert "_rememberPendingSessionModel(" in region, (
+        "modelSelect.onchange must record the explicit pick so send() can detect it"
+    )
+
+
+def test_onchange_does_not_clear_pending_pick_after_session_update():
+    """The premature clear (the #3737 bug) must be gone: onchange must NOT call
+    _clearPendingSessionModel after the /api/session/update POST."""
+    region = _model_onchange_region()
+    assert "_clearPendingSessionModel" not in region, (
+        "modelSelect.onchange must NOT clear the pending explicit-pick marker — it has "
+        "to survive until send() consumes it, else the normal pick→update→send flow "
+        "loses the explicit-pick signal and the server re-reverts the pick (#3737)"
+    )
+
+
+def test_send_consumes_pending_pick_after_reading_it():
+    """send() must clear the marker once it has read a matching pending pick, so a
+    later send of an unchanged dropdown is not treated as a fresh explicit pick."""
+    idx = MESSAGES_JS.find("_explicitPick")
+    assert idx != -1, "_explicitPick not computed in send()"
+    region = MESSAGES_JS[idx: idx + 1100]
+    assert "_clearPendingSessionModel(activeSid)" in region, (
+        "send() must consume (clear) the pending explicit-pick marker after reading it"
+    )
+    # The clear must be gated on _explicitPick (only consume a genuine, matching pick).
+    assert re.search(r"_explicitPick\s*&&[^\n]*_clearPendingSessionModel", region), (
+        "the consume-clear must be gated on _explicitPick"
+    )
+
+
+def test_send_sends_flag_only_when_explicit():
+    idx = MESSAGES_JS.find("_explicitPick")
+    region = MESSAGES_JS[idx: idx + 1300]
+    assert "explicit_model_pick:_explicitPick||undefined" in region.replace(" ", ""), (
+        "the chat/start payload must send explicit_model_pick only when truthy"
+    )
diff --git a/tests/test_model_selection_refresh_persistence.py b/tests/test_model_selection_refresh_persistence.py
index 3f3eaad3..cca70140 100644
--- a/tests/test_model_selection_refresh_persistence.py
+++ b/tests/test_model_selection_refresh_persistence.py
@@ -30,7 +30,14 @@ def test_model_selection_records_pending_state_before_async_session_update():
 
     assert pending_idx < update_idx
     assert local_model_idx < update_idx
-    assert "_clearPendingSessionModel" in body
+    # onchange must NOT clear the pending marker after the session-update round-trip.
+    # The marker has to survive until the next send() consumes it, otherwise the normal
+    # pick→update→send flow loses the explicit-pick signal and the server re-reverts a
+    # cross-family pick (#3737). The consume-clear now lives in send(), not here.
+    assert "_clearPendingSessionModel" not in body, (
+        "modelSelect.onchange must not clear the pending explicit-pick marker (#3737); "
+        "send() consumes it instead"
+    )
 
 
 def test_load_session_applies_pending_model_before_first_topbar_sync():
diff --git a/tests/test_provider_mismatch.py b/tests/test_provider_mismatch.py
index ca5c0d4d..2c1f2a29 100644
--- a/tests/test_provider_mismatch.py
+++ b/tests/test_provider_mismatch.py
@@ -1438,6 +1438,43 @@ def test_custom_namespace_model_always_preserved_on_custom_provider(monkeypatch)
     assert effective == "custom/my-local-llm"
 
 
+def test_explicit_pick_survives_profile_family_mismatch():
+    """When explicit_model_pick=True, a cross-family bare model survives
+    the profile-aware normalization instead of being rewritten to the
+    profile default (#3737)."""
+    import api.routes as routes
+
+    effective, provider, changed = routes._resolve_compatible_session_model_state(
+        "gpt-5.4-mini",
+        None,
+        profile_provider="anthropic",
+        profile_default_model="claude-sonnet-4",
+        explicit_model_pick=True,
+    )
+
+    assert changed is False, "explicit pick must not be normalized"
+    assert effective == "gpt-5.4-mini", "user's model must survive"
+    assert provider == "anthropic", "profile provider context preserved"
+
+
+def test_explicit_pick_false_allows_profile_family_normalization():
+    """Without explicit_model_pick, the same cross-family model IS rewritten
+    to the profile default (existing behavior, must not regress)."""
+    import api.routes as routes
+
+    effective, provider, changed = routes._resolve_compatible_session_model_state(
+        "gpt-5.4-mini",
+        None,
+        profile_provider="anthropic",
+        profile_default_model="claude-sonnet-4",
+        explicit_model_pick=False,
+    )
+
+    assert changed is True, "stale model must be normalized"
+    assert effective == "claude-sonnet-4", "rewritten to profile default"
+    assert provider == "anthropic", "profile provider context preserved"
+
+
 def test_stale_ui_js_does_not_inject_unavailable_option():
     """renderSession() must no longer inject a bare (unavailable) option into
     modelSelect when the session model is not in the provider list (#829).