I encountered the same issue. I play on the Nintendo Switch locally (not using a realm).
Explored a natural cave 20 chunks away from the spawn point. I ended up digging a straight line from a Skeleton Spawner within the cave back to the main hub of my base. I started working backwards placing Railroad Tracks and suddenly the straight line cave stopped a few hundred blocks short of the co-ordinates I initially started digging at.
I went back to the surface and back to the cave entrance and noticed that all the torches I had placed were gone and mobs had respawned in the exact same spot I had previously noticed them. I also noted that ores (iron and coal) had been replaced in the walls.
I then decided to "quit and save" in hopes that there was some weird issue accessing the save data. After a few minutes of seeing the "Savings, do not turn off your console" message the game crashed with the error "an unexpected issue has occurred." After returning to the game I was back to the start point where I was 3 hours prior.
What is interesting about it was that the entire session was not spent exploring the cave. I noticed in the minecraft forum post linked above a user talks about "safe" chunks close to his spawn point. I spent close to 1.5 hours within 2 chunks of my spawn and nothing from that was autosaved. The entire session seems to have been bugged since the very start.
I have also noticed that this happens randomly afterwards. I would join the world, take 10 steps, and then quit the game and save. Sometimes I was able to save properly and I would reload in the expected location, but sometimes the game would crash while saving and I would return the prior position.
Dacotah Harvey
I encountered the same issue. I play on the Nintendo Switch locally (not using a realm).
Explored a natural cave 20 chunks away from the spawn point. I ended up digging a straight line from a Skeleton Spawner within the cave back to the main hub of my base. I started working backwards placing Railroad Tracks and suddenly the straight line cave stopped a few hundred blocks short of the co-ordinates I initially started digging at.
I went back to the surface and back to the cave entrance and noticed that all the torches I had placed were gone and mobs had respawned in the exact same spot I had previously noticed them. I also noted that ores (iron and coal) had been replaced in the walls.
I then decided to "quit and save" in hopes that there was some weird issue accessing the save data. After a few minutes of seeing the "Savings, do not turn off your console" message the game crashed with the error "an unexpected issue has occurred." After returning to the game I was back to the start point where I was 3 hours prior.
What is interesting about it was that the entire session was not spent exploring the cave. I noticed in the minecraft forum post linked above a user talks about "safe" chunks close to his spawn point. I spent close to 1.5 hours within 2 chunks of my spawn and nothing from that was autosaved. The entire session seems to have been bugged since the very start.
I have also noticed that this happens randomly afterwards. I would join the world, take 10 steps, and then quit the game and save. Sometimes I was able to save properly and I would reload in the expected location, but sometimes the game would crash while saving and I would return the prior position.