Thralls falling through stonebrick ceiling tiles since latest hotfix

Game mode: Online
Problem: Bug
Region: Americas Offical 1504

Since latest hotfix, all of my thralls placed on the ceiling tiles (stonebrick) have started falling through them to the ground. they were 4 walls high on the roof, and now they are all standing halfway through the stonebrick foundations. i moved them all back and then they fell again. this is new since latest hotfix as they have been up there for a couple weeks without issue.