Panthers have qualified but will be seeded outside the top three
The Elite League will allow each Challenge Cup group winner to pick their own opponents in the quarter-finals.
Sheffield Steelers have already secured the first seed, Milton Keynes Lightning the second seed and Belfast Giants the third seed.
They will pick from seeds four to eight in turn for their last eight tie.
Nottingham Panthers are through, but their final seeding will be determined after they have faced Manchester Storm in their last group game.
“We wanted to find a way to make the group stages of the Challenge Cup as meaningful as possible, and to reward the group winners.” league chairman Tony Smith said.
“This change will do that, whilst also adding an extra element to the competition.
“Those top seeded teams will really need to think about who they want to face in the quarter-finals, who they think they will match up well against.
“Equally those teams chosen as the opponents won’t want to be seen as some kind of ‘weak link’ – it will give them an extra point to prove as they look to progress in the competition themselves.”