I honestly think the date changes are not an indicator of a/d/wl at all. Seeing as how the majority have seen daily changes over the past week, it wouldn't make sense to assume they are the accepted group, given the ~20% acceptance rate. Also, waived applicants also saw daily changes.
A much smaller number had dates that remained in October - Mid November range. I was one of them, but mine changed to 12/11. I would assume this is an indication of someone or the committee going back to review my application for final consensus.
I think the applications are just put into pools based on interviewer, submission date, or how the piles landed on someone's desk. Then they are simply reviewed again in some order, and that's why we are seeing this round of changes.