I've run into this issue twice since the 1.16.1 update, also on Realms. Two days ago, I got a chat message that the server would reset for maintenance in 5 minutes, so I logged off. When I logged back on some time later, first I had problems where I got stuck in a glitchy interaction with a door, so I re-logged. When I logged back in I had lost about an hour of progress. Today I just signed off on my own for about half an hour, and when I logged back in, I had lost about 15 minutes of progress.
Vis Major
I've run into this issue twice since the 1.16.1 update, also on Realms. Two days ago, I got a chat message that the server would reset for maintenance in 5 minutes, so I logged off. When I logged back on some time later, first I had problems where I got stuck in a glitchy interaction with a door, so I re-logged. When I logged back in I had lost about an hour of progress. Today I just signed off on my own for about half an hour, and when I logged back in, I had lost about 15 minutes of progress.