They do different routines for each compulsory level. I think it was intended to follow a certain skill progression so they will have the right form/technique when they reach optionals. There is a lot of latitude in xcel, so they aren’t getting the same progression and the judging tends to be more lenient.I thought it was because they got to do more interesting routines and tailor skills early on while the girls perfect the compulsory skills. It is stiffeling to do the same routines year after year after year I am sure.