Answered my own question. I reported an SQD discrepancy on July 17 for a flight on July 12. The adjustment just posted today so it looks like the current processing time is ~6 weeks. No notification e-mail and the adjustment posted to the original flight date.

So for my most recent SQD discrepancies reported on August 16, I guess I shouldn't expect to see them until late September.

Update: Also just received the SQD for an eUpgrade Add-on for a flight on August 15. So the processing time of these seems to be ~2 weeks.