What I see in this post is the emphasis on AFTER. Looking at the site below, and checking another, it does not look like any ballot in Michigan should be counted unless received before polls close election day. So that massive ballot dump after the fact…
In Wisconsin, it's even tighter. So where/when did those late ballots come in? (Well, we have a good idea)
It sounds like the total number of ballots that met the deadline could be known. Of course, I suppose the multi-functional Dominion could also back date ballots like the post office.
https://www.vote.org/absentee-ballot-deadlines/
Michigan:
Received by the time the polls close on Election Day.
Wisconsin:
Received by 8pm on Election Day.