If I were Ole Miss, you either telling Kiffin your in and make him sign the extension, or your out. I don’t think you can do this allowing him to still coach through the playoffs knowing he’s already signed and been announced as the next LSU coach. No matter what, he’s going to be distracted by building his staff and getting things ready at LSU if he were allowed to coach in the playoffs at LSU. Additionally, you dun the risk of Kiffin recruiting Ole Miss players to LSU.
I think what Ole Miss needs to do if Kiffin leaves for LSU is retain all the current staff through the playoffs and offer large bonuses for each game coach and/or game they win in the post season. Maybe the total package could be the sum of what ever buyout Kiffin owes Ole Miss if they win the natty. Maybe ask Saban or another experienced coach to be interim during the playoffs. Keeping the current staff, who are the ones developing the game plan and working with the players will be the best way to be successful during the post season. I understand that a head coach is important in making decisions, but we cannot forget the ones doing the actual work.