the GUI for the Aerogear unified push Server needs to be updated to reflect the transition from GCM to FCM. In the Variant configuration of UPS for Android, Some field names reflect outdated terminology pertaining to GCM which is no longer used.

notably, the following

'Project Number' has been changed to 'Sender ID'
'Google Cloud Messaging Key' is now referenced in the FCM console UI as "Server Key"

Please see attached images for examples.