The two keys can be added via group policy to suppress notifications of updates.
Hive HKEY_CURRENT_USER
Key path Software\FileMaker\FileMaker Pro\16.0\Preferences
Value name Hide New Version Notification Dialog
Value type REG_SZ
Value data 1
Hive HKEY_CURRENT_USER
Key path Software\FileMaker\FileMaker Pro\16.0\Preferences
Value name Hide Update Notification Dialog
Value type REG_SZ
Value data 1