I believe riders who just miss the required score for an invitation, or, land just out of the placings in their Regionals, get a notification that they are wait listed for the Finals class. So that way if someone ahead of them doesn’t opt to show, they can.
I have a friend who was invited by winning her Freestyle at a level, but was wait listed for the regular class of the same level. She missed the required score by hundredths of a percent at Regionals. I think a 65 was required, or, being in the top two, no matter the score? (That info is somewhere but I can’t find it just now)
So she headed to KY entered in the Champs Freestyle for sure, and WL for the other Champs class. But nobody dropped out so she didn’t end up showing in it.