Is it possible to be notified when a prerelease album is available on Apple Music? I have downloaded an album on Apple Music several months ago when it became available on pre-release. At the time, only one song was available to listen to. I had forgotten all about it and it sat amongst my albums and the release date came and went.  Weeks later, I was scrolling through my albums and I saw it there. 

Is it possible to get notified when a pre-release album is fully released? I'm using both iPad and iPhone on iOS11.
Not sure if you’d get notified if the pre-release turns into a proper release, but you can get notified when artists you usually listen to release new stuff. Chances are that the upgrade from pre-release to actual release generates a notification as well.

You can configure the notifications by following the Apple Support Document, Get Apple Music notifications.