I got the same problems for a few days now.
Official server 3179, PS4.
I bought the game like 1 week ago, got raided after 2 days so we did move our bases to the other side of the map closer to our allies.
So when i made my new base, i did put ceillings on the 1st,2nd floors and on the roof.
Yesterday and 2 days before that, the ceilling on the 2nd floor and roof did disappear (1st floor didnt, all of them got a pillar)
Both of the days on the same spot and the same ceillings.
Nothing got stolen, no info in the event logs.
Yesterday i got log, because i noticed the missing ceillings before the enemy did reach the top of my building.
It will be pretty sad that my loot gets stolen when they are missing again and im not online.
Edit:: The first disappearing happened when i logged in, so might be because of ending the session the night before it.
The disappearing yesterday happened after the update or after logging out that night before the update.
Im sure its a bug, because its the same spot every time and there are no logs of it.