I already made a huge search and don\'t know why Google Play are not letting me update my Prod app. Their error message does not make too much sense for me, actually I don\'
This is because your new build has a targetSdkVersion (22) lower than your current live build (23) in the manifest:
targetSdkVersion 23 is for Android 6+ where there is a new way to manage permissions : http://developer.android.com/training/permissions/requesting.html
So your current live users having Android 6+ are using the new permission system and it seems this is a problem for Google to downgrade those users to targetSdkVersion 22 where there is the old permission system.
So to fix it, you should update your new build to use targetSdkVersion 23 :
and so make sure you manage the new permission system.