Mbappe is a great player and I'm sure Carlo Ancelotti is delighted to have him now. His rotation is quite wide right now. Considering that Arda Güler plays great in the wing position, they have a lot of options and a young average age. We can say that Ancelotti has established the squad for the next 5 years.
Maybe, maybe not they are yet to finalise it, they are used to having alot of talented player no doubt and about the rotation , if I get it right I.e rotating mbappe for other player which I don't think it will be very possible although they might want to rest him but rotating him frequently might not be very possible IMO but if it turns out to be true then I hope he adapt without losing form ( don't forget about hazard ,although his case was different..)