My queue is empty except for 4* non-champ characters who are already at 5 covers:
XF 
4 
Get ready for that to happen more and more. And pretty soon, it will happen with 5* characters as well! You’ll never be able to draw the OML yellow you need, but you’ll draw the OML black and red that you definitely don’t need many, many times. 
It’s an unfortunate reality of the 4* transition. You’ll be forced so sell a great many 4* covers, so don’t worry about it too much. There will always be more 4*s behind those.