I had the same issue when the update first launched. I think it is tied to the new online infrastructure they implemented.
On the title screen, before you load into your game there is an indicator in the lower left showing your connection status. If you wait 5-10 seconds after loading the title screen you will see it show you as connected. Since I've started waiting for that before starting my game I haven't had the issue.
I think the problem is the game hasn't finished logging you into the various services (Steam and Epic), so it doesn't have your ID. This causes it to spawn you in a new body. Waiting for it to establish those connections keeps your ID the same and spawns you back in the proper body.
Hope this resolves it for you like it has for me.
No idea. I'm paranoid and always do a manual save before quitting.