Those that have charged on 9/1 have been patient enough. Their credits should have long posted based on the timeline when they posted since the beginning of the year which was usually within 2 or 3 days.

There does seem to be an issue for September. I used $20 (Brilliant), $10 (Marriott personal), and $5 (Hilton) cards today, all at local establishments where I've used these credits and gotten the emails and credits successfully every month. Not a single email received. Won't be surprised if the credits are delayed or need to be done manually eventually.