https://www.fantasyflightgames.com/en/news/2016/4/15/the-championship-series/
One of the other articles released today details the tournament structure for the various competitive event levels, and it looks like starting this year, at the very least the US nationals and North American Continental championships will be using Custom Structures(as defined in the tournament document, anything that doesn't conform to standard or advanced), and will instead have a graduated cut after 6 rounds. As far as I'm aware this is not how they've worked in previous years?
So, after 6 rounds, X number of players, plus some number of players with the same number of Tournament Points as the Xth player, will go to another smaller set of swiss the next day, followed by the cut to elimination.
Edited by Otacon