I had a stay in October that didn't post, and I called in and was assured it would be posted. After 3 days it wasn't there, so I called again and it did appear with 2-3 hours. I have to keep a much closer watch on Hyatt postings than I ever have on my UA and AA accounts.
Right now I have two other stays this month that haven't posted (Nov 3 and 13 at the same property), but I'm going to save everything up for the end of the month and just deal with it all at one time.