Google aab signing
This is just a quick note to self :-)
The profile used for the Build > Generate Signed App Bundle or APK in AndroidStudio needs to have the Debuggable option set to false or it will be rejected on upload with the rather unhelpful message
The Android App Bundle was not signed.
Obviously this means the default Debug profile can't be used for uploading to the Google Play Console.
And yes, the message could be more helpful...