Game mode: [Online]
Region: [Official 1510 PVE Server]
Upgraded foundations to Khitan last night. When signed in today, two improved furnaces, two carpenter’s benches, two grinders, a large campfire, a large chest, Khitan Artisan table, and a cupboard all disappeared. The thralls attached and items inside also gone. There was no event log that the items were destroyed and I have not had a purge for weeks but there was no damage to the structure itself only the items inside gone.
It certainly did not remove all crafting stations and items but all items that were missing were sitting at least partially on the Khitan Wedge foundation.