No plans for Spotify this is the opposite of Self Hosting :p And not really compatible with the offline first approach the app use.

But I know one user have built a server that expose Spotify as Subsonic server to achieve this.

Maybe you can convince him to make his project public :)

https://support.symfonium.app/t/sync-terminates-early/2572

No, it’s a closed source app. And even then it uses closed source Google libraries that are incompatible with F-Droid.

Yes proper bug report with logs on the forum, but the app have nothing really related to BT, was you phone updated to Android 14?