Logged into old save, BM base gone. But Chunk reset is Disabled?

[Sally McSaggyTits]

So I loaded up an old Version 21.2 save I was working on since last year. Made sure I installed the older version to ensure compatibility.

I get in, my main base is there, everything is fine. I have an inactive Land Claim Block there (not sure why it's inactive since I'm sure it was the only one I placed in the map), and even though the LCB doesn't cover my entire base, it was all there.

Then, I go to my blood moon base that night as it's BM night, realise it's entirely gone and the area is reset to default. It was in a small farm patch with a harvester. It was there when I logged out last time, and I hadn't started a quest in the area. I assumed it was a chunk reset, but I confirmed my chunk reset setting is disabled.

More confusingly, I was mining out in the nearby desert for a while, went back to base and logged out. I just logged in there again to do more mining at the same spot, and the hole I dug is gone, again as if the chunk reset.

I dug a new hole in the same rough area, logged out and logged back in to test it and the hole is still there.

I'm now concerned about building anything outside of my base as there seems to be some kind of chunk reset going on. Any ideas what's happening? The mining hole is annoying but not a big deal since I haven't lost anything, but I don't want to lose another Blood Moon base for nothing.

I also don't get why if it's resetting chunks that it hasn't touched my main base. I don't even have a bed down in it.

Any help is appreciated.