In my realm it seems I can "control" when this happens. The disconnect and roll back always happens when I am leaving nether. It loads the overworld, then it says disconnect. Loading again and it has rolled back to a backup. But it does not always happen (it did before, but maybe the latest updates has solved parts of the problem). I realized it always happens when I was in a certain area in Nether where I went to to mine black stone. If I were in other areas, it never disconnects. I tried this a few times. Went to the black stone area and tried to mine, just stay there for some time, kill some mobs etc. Different things. And if I only mined a few blocks and did not kill any mob, it never disconnects. But if I mine more, stayed longer, killed more mobs, it disconnects. Or even only went there to mine like half a stack quickly and then went back, it also disconnects. But any other area works fine. Also other areas with black stone. So I do not go back to that troublesome area any longer, and now I do not have the problem any longer with disconnects.
This happens when I am alone on Realm or we are two players. Both on PC and PS4/PS5.
Still a big issue. Every time I enter Nether, I do not stay for long since I never know if it will crash and roll back when I return from it. Better to stay there for shorter periods, but more frequent instead. Every time I return and it works... its like winning a lottery.
Is this issue related to REALMS-1489? That issue also relates to disconnects and roll backs, but is only when using portals to travel back from Nether. This is part of the description for this ticket: "Traveling between dimensions". That issue has been active since August last year.
In my case the disconnect and rollback only happens when travelling from Nether to overworld. My findings so far:
It also happens when downloading the world from my realm and play it locally on my PC. Windows crash report does not say much though.
It seems like it mostly happens when using my second portal which is closer to my village and Iron farm (also a village). This portal is also closer to my sorting machine/base where more complex redstone and a lot more items are located. Not sure if this has an impact.
I get a feeling that the more time spent in Nether increases the risk of crashing
In some rare cases it does not disconnect immediately when traveling back, but instead the overworld is loaded and then disconnected 1-2 minutes later.
The rollback most often loads a backup before I went to the Nether. But in rare occasions a backup when I just entered the Nether is loaded.
It happens when I am alone in the realm and when we are two players and one of us travels back from the Nether
It happens on Android, PC, PS4 and PS5