User blog comment:B214/Question and Answers 6/@comment-185.112.105.215-20161218170008/@comment-10330822-20161220214837

Yeah, odds are Ise is going to be so powerful at that point, Rias's own strength will be rather irrelevant. Besides, I feel they are going to break the seal long before its time is up, so they can save the other leaders. That might be something they do at the end of the series.