Hey, the school needs financing!

the entire Erik/Charles relationship is defined by periods of friendship broken up by periods of putting on silly costumes and trying to destroy the world

I think that will remain the same in any timeline. (Especially the costumes. Older Erik even wears a dramatic opera coat during the sentinel apocalypse!) Which is why older Charles didn't even bother to warn younger Charles that Erik would double cross him now and then when they're on the same side and not to let that get to him too much anymore, because he knows younger Charles knows that by now already.

...do we think Hank was a virgin before he and Charles started to have sex now and then during their time as not!heroin addicts together? Because he came across as somewhat virginal with Raven, and afterwards would have had hangups because of his Beast shape...