title: How to unsubscribe user from FCM without calling FirebaseMessaging.getInstance().unsubscribeFromTopic
body: <p>I'm using FCM in my Android Application and I am satisfied with it. I'd like to know is there a way to migrate user/group of users from one topic to another without manually calling FirebaseMessaging.getInstance().unsubscribeFromTopic() on those devices? I'd like to have this possibility on the server-side. Thank you for your replies.</p>