This Sunday will be Chris Jericho’s last match in WWE for quite a while, and possibly forever. That is Jericho’s last match before he takes a long leave of absence. There is a chance that he will be on RAW the following night, possibly to explain his leave in-character.
This basically confirms that Jericho will not be winning the title off of John Cena at SummerSlam, unless he lost it the next night on RAW which is possible.
It’s likely that Jericho will return some time in the future, but there is the possibility that he will not. There are no details on when (or, if) he plans on returning as of right now.