In D1N we had only one change at this age and weight. It was a scratch the day of the tournament. So, I am assuming you are talking about the D1S??? It is my understanding that changes after the seeding meeting can only be made for administrative errors on the part of the host club running the tournament. I would think in most cases such admin errors would be caught before the day of the event. We had several change requests made after the seeding meeting in the North which were denied for this reason. I had one angry parent in the North who didn't understand why they weren't allowed to move a weight class the day of our tournament.