diff --git a/package-lock.json b/package-lock.json
index 74e1302..dac42c0 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@ulms/api-clients",
-  "version": "7.14.0",
+  "version": "7.14.0-dev.1-ULMS-3278",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@ulms/api-clients",
-      "version": "7.14.0",
+      "version": "7.14.0-dev.1-ULMS-3278",
       "license": "MIT",
       "dependencies": {
         "axios": "1.6.2",
diff --git a/package.json b/package.json
index 68a23e2..cb56b34 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@ulms/api-clients",
-  "version": "7.14.0",
+  "version": "7.14.0-dev.1-ULMS-3278",
   "description": "JavaScript API clients for ULMS platform",
   "keywords": [],
   "homepage": "https://github.com/foxford/ulms-api-clients-js#readme",
diff --git a/src/mqtt.js b/src/mqtt.js
index 0c6f531..121f71d 100644
--- a/src/mqtt.js
+++ b/src/mqtt.js
@@ -46,7 +46,7 @@ class MQTTClient {
       })
     const mqttVersion =
       isBigIntSupported && !isOldBrowserVersion ? '5.9.1' : '3.0.0'
-    const source = `https://ulms-static.foxford.ngcdn.ru/prod/js/mqtt@${mqttVersion}/dist/mqtt.min.js`
+    const source = `https://static.ngcdn.ru/js-libs/mqtt@${mqttVersion}/dist/mqtt.min.js`
 
     return retry(() => loadScript(source))
   }
diff --git a/src/ulms.js b/src/ulms.js
index 88cfcbe..e53aeea 100644
--- a/src/ulms.js
+++ b/src/ulms.js
@@ -159,10 +159,11 @@ class ULMS extends BasicClient {
 
   /**
    * Account properties enum
-   * @returns {{ONBOARDING: string}}
+   * @returns {{LAST_SEEN_MESSAGE_ID_BY_ROOMS: string, ONBOARDING: string}}
    */
   static get accountKeys() {
     return {
+      LAST_SEEN_MESSAGE_ID_BY_ROOMS: 'last_seen_message_id_by_rooms', // todo: deprecated key
       ONBOARDING: 'onboarding',
     }
   }