Days Later: Still working properly for me, no logout, no problems (well, none about the logouts) now for about a week. I see that just about when things got working again, there was an AppleTV tvOS update to 16.5 (20L563) from the tvOS 16.4.1 (20L498).  It may be that this change cleared up the cache issue... at least for now... The only other changes I note in Pandora behavior this week are that it takes much longer to "time out" and stop playing music (at least a full day), and when it does, it does not display the "Are you still listening?" screen... it just stops. And will not restart without selecting a different "station". Navigation is normal in Pandora after the music stops, but you can't just resume the station you had been on. Dave, looks like you have a moving target. But that's always the case, eh?

Tucan, have a look in SETTINGS>System for your tvOS version... if not at 16.5 yet, update and report your findings.