SOLVED: Server Owners: How to handle savedata migration between versions?

[Byrnorthil]

I just manually updated my dedicated self-hosted server (Linux arm64) to 1.22.2, and when I relaunched my savefile seems to have gone missing. When I rebooted it the server said effectively "existing savefile not found, creating a new one" and sure enough when I tried to connect with my client I was no longer whitelisted and it was a brand new world. I will note that because it's the ARM version I was not able to use the default installer and had to manually copy ARM files over and run the server myself like so:

dotnet ./VintagestoryServer.dll --dataPath /var/vintagestory/data/ --port=25565

My group had only played for 2 hours a couple nights ago, so it's not a huge loss if my data really is gone, but I'd like to know which of these is most likely and how I can avoid it in the future:

1. I somehow accidentally deleted my world data during the migration process. I don't find this particularly likely since I set the datapath as /var/vintagestory/data/ which is completely separate from the server installation (/home/$USER/server/).
2. DISCOVERED: My save somehow ended up in ~/.config/VintagestoryData/. I have no idea why but it seems to be intact.
3. Savefiles from different minor versions are incompatible and the game will just override your existing save when you switch versions.
4. The server failed to write to the data directory when I shut it down and failed to warn me about this. Edit: I'm not counting this out entirely, but I did some testing and it seems to be writing to the directory just fine right now, so if this was the culprit then it seems to have solved itself.
5. Something else I haven't thought of.

Ultimately it is on me for not making a backup and like I said it's not a huge loss either way, but I'd really like to automate any fix I end up having to do with a script and if anyone's had similar troubles I'd appreciate the insight.

Edited yesterday at 12:06 AM by Byrnorthil
Found my save, will make a new post.