diff --git a/js/qdreader_sign_autman.js b/js/qdreader_sign_autman.js
index 217c125..7f16874 100644
--- a/js/qdreader_sign_autman.js
+++ b/js/qdreader_sign_autman.js
@@ -4,7 +4,7 @@
 //[author: Hermes]
 //[service: BOSS]
 //[class: 工具类]
-//[version: 2.4.1]
+//[version: 2.4.2]
 //[platform: web,qq,wx,tg,tb,fs,we]
 //[public: false]
 //[price: 0]
@@ -124,6 +124,23 @@ function currentUserId() {
 function currentOwnerId() {
     return currentUserId()
 }
+function currentIsAdmin() {
+    try { if (typeof isAdmin === "function" && isAdmin()) return true } catch (e) {}
+    try { if (typeof sender !== "undefined" && sender && typeof sender.isAdmin === "function" && sender.isAdmin()) return true } catch (e2) {}
+    try { if (typeof Sender !== "undefined" && Sender && typeof Sender.isAdmin === "function" && Sender.isAdmin()) return true } catch (e3) {}
+    return false
+}
+function looksLikeLegacyFallbackOwner(owner) {
+    owner = trim(owner)
+    if (!owner) return false
+    if (owner === "__qdreader_default_owner__") return true
+    if (/^[A-Za-z0-9._-]{1,32}$/.test(owner) && !/^\d{5,}$/.test(owner)) return true
+    return false
+}
+function canRepairBinding(oldOwner, me) {
+    if (!oldOwner || oldOwner === me) return true
+    return currentIsAdmin() && looksLikeLegacyFallbackOwner(oldOwner)
+}
 function currentUserDebug() {
     var parts = []
     var fns = ["GetUserID", "GetChatID", "GetImType", "ImType", "GetUsername"]
@@ -242,7 +259,7 @@ function contentText() {
 }
 function usage() {
     return [
-        "启点读书签到插件 v2.4.1",
+        "启点读书签到插件 v2.4.2",
         "【一级菜单】",
         "账号管理：启点账号",
         "执行查询：启点查询",
@@ -658,6 +675,10 @@ function handleSaveCookie(arg, store, bind) {
             oldOwner = ""
             lines.push("检测到 uid: " + uid + " 只有旧绑定没有CK，已自动清理残留绑定")
         }
+        if (store[uid] && oldOwner && oldOwner !== me && canRepairBinding(oldOwner, me)) {
+            lines.push("检测到 uid: " + uid + " 旧绑定来自历史兜底标识 " + maskUid(oldOwner) + "，已修复为当前用户")
+            oldOwner = ""
+        }
         if (store[uid] && oldOwner && me && oldOwner !== me) {
             lines.push("无权更新 uid: " + uid + "（该账号已绑定其他用户）")
             continue
diff --git a/plugins/qdreader/qdreader_sign_autman.js b/plugins/qdreader/qdreader_sign_autman.js
index 217c125..7f16874 100644
--- a/plugins/qdreader/qdreader_sign_autman.js
+++ b/plugins/qdreader/qdreader_sign_autman.js
@@ -4,7 +4,7 @@
 //[author: Hermes]
 //[service: BOSS]
 //[class: 工具类]
-//[version: 2.4.1]
+//[version: 2.4.2]
 //[platform: web,qq,wx,tg,tb,fs,we]
 //[public: false]
 //[price: 0]
@@ -124,6 +124,23 @@ function currentUserId() {
 function currentOwnerId() {
     return currentUserId()
 }
+function currentIsAdmin() {
+    try { if (typeof isAdmin === "function" && isAdmin()) return true } catch (e) {}
+    try { if (typeof sender !== "undefined" && sender && typeof sender.isAdmin === "function" && sender.isAdmin()) return true } catch (e2) {}
+    try { if (typeof Sender !== "undefined" && Sender && typeof Sender.isAdmin === "function" && Sender.isAdmin()) return true } catch (e3) {}
+    return false
+}
+function looksLikeLegacyFallbackOwner(owner) {
+    owner = trim(owner)
+    if (!owner) return false
+    if (owner === "__qdreader_default_owner__") return true
+    if (/^[A-Za-z0-9._-]{1,32}$/.test(owner) && !/^\d{5,}$/.test(owner)) return true
+    return false
+}
+function canRepairBinding(oldOwner, me) {
+    if (!oldOwner || oldOwner === me) return true
+    return currentIsAdmin() && looksLikeLegacyFallbackOwner(oldOwner)
+}
 function currentUserDebug() {
     var parts = []
     var fns = ["GetUserID", "GetChatID", "GetImType", "ImType", "GetUsername"]
@@ -242,7 +259,7 @@ function contentText() {
 }
 function usage() {
     return [
-        "启点读书签到插件 v2.4.1",
+        "启点读书签到插件 v2.4.2",
         "【一级菜单】",
         "账号管理：启点账号",
         "执行查询：启点查询",
@@ -658,6 +675,10 @@ function handleSaveCookie(arg, store, bind) {
             oldOwner = ""
             lines.push("检测到 uid: " + uid + " 只有旧绑定没有CK，已自动清理残留绑定")
         }
+        if (store[uid] && oldOwner && oldOwner !== me && canRepairBinding(oldOwner, me)) {
+            lines.push("检测到 uid: " + uid + " 旧绑定来自历史兜底标识 " + maskUid(oldOwner) + "，已修复为当前用户")
+            oldOwner = ""
+        }
         if (store[uid] && oldOwner && me && oldOwner !== me) {
             lines.push("无权更新 uid: " + uid + "（该账号已绑定其他用户）")
             continue
diff --git a/tests/qdreader_plugin.test.mjs b/tests/qdreader_plugin.test.mjs
index d7121eb..ebba8c3 100644
--- a/tests/qdreader_plugin.test.mjs
+++ b/tests/qdreader_plugin.test.mjs
@@ -5,7 +5,7 @@ import vm from 'node:vm';
 const pluginPath = new URL('../plugins/qdreader/qdreader_sign_autman.js', import.meta.url).pathname;
 const code = fs.readFileSync(pluginPath, 'utf8');
 
-function runPlugin({ content = '', store = {}, bucketStore = {}, requests = [], userId = 'user-a', listens = [], senderOverrides = {}, globals = {} } = {}) {
+function runPlugin({ content = '', store = {}, bucketStore = {}, requests = [], userId = 'user-a', listens = [], senderOverrides = {}, globals = {}, admin = true } = {}) {
   const replies = [];
   const calls = [];
   let requestIndex = 0;
@@ -14,7 +14,7 @@ function runPlugin({ content = '', store = {}, bucketStore = {}, requests = [],
       reply: (msg) => replies.push(String(msg)),
       getMessage: () => content,
       getContent: () => content,
-      isAdmin: () => true,
+      isAdmin: () => admin,
       getUserID: () => userId,
       listen: () => (listenIndex < listens.length ? listens[listenIndex++] : 'q'),
     };
@@ -178,15 +178,38 @@ test('quick submit can re-add cookie when old binding remains but cookie was man
   assert.equal(JSON.parse(r.store.qdreader_user_bind_json)['12345'], 'user-a');
 });
 
-test('quick submit still rejects overwrite when cookie and another owner binding both exist', () => {
+test('quick submit still rejects overwrite when cookie and real another owner binding both exist', () => {
   const store = {
     qdreader_cookie_json: JSON.stringify({ '12345': cookie }),
-    qdreader_user_bind_json: JSON.stringify({ '12345': 'old-user' }),
+    qdreader_user_bind_json: JSON.stringify({ '12345': '987654321' }),
   };
   const r = runPlugin({ content: '启点ck ' + cookie.replace('qdh=qdh', 'qdh=newqdh'), store, userId: 'user-a', listens: ['n'] });
   assert.match(r.replies.join('\n'), /无权更新 uid: 12345/);
   assert.equal(JSON.parse(r.store.qdreader_cookie_json)['12345'], cookie);
-  assert.equal(JSON.parse(r.store.qdreader_user_bind_json)['12345'], 'old-user');
+  assert.equal(JSON.parse(r.store.qdreader_user_bind_json)['12345'], '987654321');
+});
+
+test('quick submit can repair legacy fallback owner when admin submits existing cookie', () => {
+  const store = {
+    qdreader_cookie_json: JSON.stringify({ '12345': cookie }),
+    qdreader_user_bind_json: JSON.stringify({ '12345': 'chickliu' }),
+  };
+  const r = runPlugin({ content: '启点ck ' + cookie.replace('qdh=qdh', 'qdh=newqdh'), store, userId: 'real-user', admin: true, listens: ['n'] });
+  assert.match(r.replies.join('\n'), /旧绑定来自历史兜底标识/);
+  assert.match(r.replies.join('\n'), /CK更新成功/);
+  assert.equal(JSON.parse(r.store.qdreader_user_bind_json)['12345'], 'real-user');
+  assert.match(JSON.parse(r.store.qdreader_cookie_json)['12345'], /qdh=newqdh/);
+});
+
+test('non-admin quick submit still rejects existing cookie bound to legacy fallback owner', () => {
+  const store = {
+    qdreader_cookie_json: JSON.stringify({ '12345': cookie }),
+    qdreader_user_bind_json: JSON.stringify({ '12345': 'chickliu' }),
+  };
+  const r = runPlugin({ content: '启点ck ' + cookie.replace('qdh=qdh', 'qdh=newqdh'), store, userId: 'real-user', admin: false, listens: ['n'] });
+  assert.match(r.replies.join('\n'), /无权更新 uid: 12345/);
+  assert.equal(JSON.parse(r.store.qdreader_user_bind_json)['12345'], 'chickliu');
+  assert.equal(JSON.parse(r.store.qdreader_cookie_json)['12345'], cookie);
 });
 
 test('quick submit rejects save when Autman JS has no user identity', () => {
@@ -422,11 +445,11 @@ test('unbound global cookies are not visible or usable by normal users', () => {
 test('user cannot overwrite another user bound cookie', () => {
   const store = {
     qdreader_cookie_json: JSON.stringify({ '12345': cookie }),
-    qdreader_user_bind_json: JSON.stringify({ '12345': 'user-a' }),
+    qdreader_user_bind_json: JSON.stringify({ '12345': '987654321' }),
   };
   const newCookie = cookie.replace('sessionyw=s', 'sessionyw=changed');
   const r = runPlugin({ content: '启点ck ' + newCookie, store, userId: 'user-b' });
   assert.match(r.replies.join('\n'), /无权更新 uid: 12345/);
   assert.equal(JSON.parse(r.store.qdreader_cookie_json)['12345'], cookie);
-  assert.equal(JSON.parse(r.store.qdreader_user_bind_json)['12345'], 'user-a');
+  assert.equal(JSON.parse(r.store.qdreader_user_bind_json)['12345'], '987654321');
 });