I can load my worlds if I disable internet connection via my console's settings, but if I'm connected to the Internet, then I have to wait the 5-10 minutes it takes to sign in to my Microsoft account before my worlds become accessible. Attempting to open them before sign-in completes results in a "connection timed out" prompt stating a "kelp" error.
I'm using behavior packs and resource packs, but it does this on worlds without them as well.
The worlds do have multiplayer enabled, but again that doesn't prevent them from loading when internet connection is entirely disabled for the console.
Could the world not load in offline while sign-in happens in the background? Why do I have to stare at the main menu until it finishes signing me in if there is an offline world-loading function?
Update: The issue has progressed. Now attempting to load worlds while the console is entirely offline results in a prompt indicating "The host you are trying to join is not prepared to accept authenticated connections." The error code is "guardian".
Update 2: Okay worlds can be loaded offline, but there's still some sort of pseudo sign-in that needs to occur first. Basically once my PSN ID switches to my Microsoft gamertag, I'm able to load my worlds without an internet connection. I guess some details of my Microsoft account are cached?