Yeah, so I have local accounts for my family, but only the last person signed in can get back in if the Internet goes down. We still have temporary access to most of the media, but it sucks.

I’ll probably get the details wrong but my understanding is that when you sign in, you get an authorization token. That token is valid for some period of time, let’s say 48 hours. You can use that cached token but let’s say it’s on your phone and not your TV. Maybe you haven’t used Plex on the TV this week. Want to use your TV, out of luck. Want to use a different local account, out of luck. Want to use Plex longer than the token is good for, out of luck.