Yep, looks pretty much like this is standard behavior.
In addition to check that I used LCS issue search but can't find any similar issues documented there... I also saw (checked for references to the class InventCostClosing) that the sync logic is not there for a long time. I'd suggest you to get in touch with your var/isv or directly log an issue with Microsoft. I still think that it's very weird to drop-create the sp and don't see a good reason for that...