The only way to be relegated with avQ decreasing is if the game sell the high avQ players ... (+ 100%?) as many of you know, the % that the players have is relative to an internal value, if you are relegated, a 5* becomes 6* ...

Well.. as always, IMO as I said there are different things that can be done but my option would be close trainings for 8* players and decrease levels of training and building if no promotion...