Replanting six inches off the rubber? That's not what I saw, and I even looked at it in super slo-mo on my DVR.
She was starting with the pivot foot on the front side of the pitcher's plate. The foot would come up and would lose contact with the plate prior to release. That is not necessarily illegal under NCAA rules. The pivot foot may lose contact if the pivot foot is not "gaining distance toward home plate", to quote their rule.
To me, it didn't look like her pivot foot was moving toward home plate. It was more of a straight up and down movement. I would have to disagree that the foot was being "planted six inches closer to home plate".
Not to say that there wasn't some hinckey foot movement at the start of her motion. This seems common with Michigan pitchers and I've often wondered if it's something they're being taught. Many of them seem to have unusual rocking motions as they start their pitch.
(And let's not forget...they're Michigan. That automatically makes them scoundrelous cheaters and nefarious villains.)
What I did see on the slo-mo was that she seemed to not only lose contact with the pitcher's plate, which can be legal, but also with the ground, which is not. On some pitches there might have been a leap mixed in there, too, with both feet being airborne at the same time. Kind of hard to tell for sure on the video. And if it's hard to tell with multiple slo-mo replays from the comfort of my BarcaLounger, you have to wonder how hard it would be to see on the field in real time.
Funny thing about illegal pitch enforcement in NCAA softball. Remember a few years ago when illegal pitches were called at an unprecedented rate? That was the result of the coaches whining about IP's and forcing the NCAA to instruct umpires to crack down. So they did...for every teeny-tiny technical violation.
The coaches got exactly what they wanted, except now their own pitchers were getting busted just as often as the "cheaters" they had hoped to stop. So they whined again. The over-the-top, to-the-letter-of-the-law enforcement was dialed back. Minor technical violations were to be ignored, stuff like losing contact with the pitcher's plate but not gaining distance toward home, or barely losing ground contact on the delivery.
NCAA softball has many rules that came about because the coaches wanted it that way. Their opinion is that it's "their game" and it needs to be called "their way". Some of these rules have trickled down to youth softball, some haven't- yet. The rules about batters not having to avoid pitches on a hit batter, coaches being penalized for filling out a line-up card incorrectly, or players getting penalized for wiping out marked lines on the field, to name just a few, all originated at the NCAA level, based on coach complaints that their opponents were getting some kind of an advantage.
Make no mistake about it: Umpires at the NCAA level are to call games exactly how the rules committee- which is driven by coach's input- tells them. If they don't, then they will not be working NCAA games.