Small Progress reset after constructing in the Outpost?

So I was being naughty last night and with using the settileprotection command I was doing a little building in the outpost of my universe. I wanted to build a little room in that gap between terramart ant the sign stand, to put some items from mods in for use at the outpost.

So, I know that if you leave something in the fridge for example it'll be gone when you come back cus it sorta resets (use the fridge as my example cus it happened to me (With quite a lot of food!) and other people quite often apparently.
I really should have tested by maybe just removing some blocks or something and going away somewhere but for some reason I went straight to staying up late last night building this room and now surprise surprise it's gone haha

The weird thing is though, just before building that room i'd talked to penguin Pete to get my ftl drive repaired (pretty close to the start with this char, she's new), but when I opened the game today the ship was still junked up and I had to talk to him again. didn't have to redo the mining facility or anything.
in looking this up I found posts about people losing all their progress from shut downs so I'm not sure if it's similar to that but I just didn't lose anything else. just literally the last thing I did.

I was just hoping to understand a little more about HOW and why the outpost resets like this. because I've seen that with new characters the outpost is still all occupied with everything you did with the previous characters. which is pretty interesting.
I would understand if like maybe getting a new artifiact or something reset it by loading a fresh map file or something but this all seems to be a bit beyond my current knowledge.
Thanks for reading!

 

Thank you so much for your reply! it explains a lot. and I hope it helps clue things in for anyone else confused about this!