And just to add detail, because I found it confusing when I first joined Lemmy: local shows posts from all communities on your instance, and all shows posts from all instances (your instance is federated with).

I tried out different apps because of the autoloading of new posts that happens on the site. I think that might have been fixed in the update, but now I’m having issues logging into lemmy.world on the site, because if the update. I keep reminding myself it’s early days and things will get smoother soon.

I literally just joined about an hour ago, so take my comment with a grain of salt, but maybe you can manually track the communities you sub to on your current instance in case that happens? I did some reading and it seems possible to set up something like an RSS feed for Lemmy communities, so you would still be able to view activity without an account (if you instance goes down), and you have something documenting the communities you are interested in. Sorry if this is not useful, just trying to do my part and be more active here.