Top half of teams all host the bottom half in a 1/16, 2/15 etc format.
If there are 3 or 4 teams in play, top team hosts #4 team, #2 hosts #3 and two winners meet in champ game. The rest of the teams play 5 vs 16, 6 vs 15, etc but aren’t eligible for the CCG.
So for the ACC this year it might look like this: Clemson hosts Pitt, Miami hosts SMU. Winners face off in CCG.
Rest of the teams play each other except FSU. They can find an FCS team to play or just not play a 12th game. They aren’t going bowling so who cares.