diff --git a/apps/api/src/services/ollama_auto_recovery.py b/apps/api/src/services/ollama_auto_recovery.py
index 9b3dc4d8..167eeb39 100644
--- a/apps/api/src/services/ollama_auto_recovery.py
+++ b/apps/api/src/services/ollama_auto_recovery.py
@@ -150,8 +150,8 @@ class OllamaAutoRecoveryService:
             current_primary=self._current_primary,
         )
 
-        # 若 primary 不是 ollama，立刻評估一次（不等 30s interval）
-        if self._current_primary != "ollama":
+        # 若 primary 不是 Ollama，立刻評估一次（不等 30s interval）
+        if not self._is_ollama_primary(self._current_primary):
             try:
                 await self._check_and_recover()
             except Exception:
@@ -217,9 +217,9 @@ class OllamaAutoRecoveryService:
             # Redis 持久化（跨重啟恢復）
             await self._persist_primary(provider)
 
-        # 2026-05-04 ogt: B5/B6 修復 — 判斷改用 startswith("ollama_")
+        # 2026-05-04 ogt: B5/B6 修復 — 判斷改用 _is_ollama_primary()
         # 原設計：provider != "ollama"，但 callback 傳 "ollama_gcp_a" → 永遠觸發 tracking
-        if not provider.startswith("ollama_"):
+        if not self._is_ollama_primary(provider):
             # 切換到非 Ollama（gemini/nemotron/claude）→ 重置 counter，開始監控恢復
             self._consecutive_healthy = 0
             logger.info(
@@ -302,6 +302,11 @@ class OllamaAutoRecoveryService:
     def is_running(self) -> bool:
         return self._task is not None and not self._task.done()
 
+    @staticmethod
+    def _is_ollama_primary(provider: str) -> bool:
+        """Return true for both legacy "ollama" and ADR-110 provider names."""
+        return provider == "ollama" or provider.startswith("ollama_")
+
     # -------------------------------------------------------------------------
     # 背景監控迴圈
     # -------------------------------------------------------------------------
@@ -359,7 +364,7 @@ class OllamaAutoRecoveryService:
 
             if (
                 self._consecutive_healthy >= self._stable_count_required
-                and not self._current_primary.startswith("ollama_")
+                and not self._is_ollama_primary(self._current_primary)
             ):
                 await self._switch_back_to_ollama()
         else:
diff --git a/apps/api/tests/test_ollama_auto_recovery.py b/apps/api/tests/test_ollama_auto_recovery.py
index 72055ac0..49ad649a 100644
--- a/apps/api/tests/test_ollama_auto_recovery.py
+++ b/apps/api/tests/test_ollama_auto_recovery.py
@@ -22,7 +22,7 @@ OllamaAutoRecoveryService 單元測試 - P1.1d
 from __future__ import annotations
 
 import asyncio
-from unittest.mock import AsyncMock, MagicMock, patch
+from unittest.mock import AsyncMock, MagicMock, call, patch
 
 import pytest
 
@@ -451,7 +451,7 @@ class TestRedisPersistence:
 
     @pytest.mark.asyncio
     async def test_set_current_primary_persists_to_redis(self):
-        """set_current_primary("gemini") → 寫 Redis ollama:current_primary"""
+        """set_current_primary("gemini") → Phase A 雙寫新舊 Redis key"""
         svc, _, _ = _make_service(current_primary="ollama")
         mock_redis = AsyncMock()
         mock_redis.set = AsyncMock()
@@ -459,7 +459,12 @@ class TestRedisPersistence:
         with patch("src.core.redis_client.get_redis", return_value=mock_redis):
             await svc.set_current_primary("gemini")
 
-        mock_redis.set.assert_awaited_once_with("ollama:current_primary", "gemini")
+        mock_redis.set.assert_has_awaits(
+            [
+                call("platform:ollama:current_primary", "gemini"),
+                call("ollama:current_primary", "gemini"),
+            ]
+        )
 
     @pytest.mark.asyncio
     async def test_set_current_primary_same_value_no_redis_write(self):