pukunui
Legend
Yeah.The AL modules have up to a 5 level spread, so very necessary there!

It would be nice if WotC provided adventure difficulty scaling suggestions in the hardcovers, but it's not that hard to figure out how difficult a given encounter should be using the DMG encounter guidelines and then adjust accordingly. (If Encounter A should be a Medium encounter for four level 5 PCs, but you've got four level 6 PCs, then figure out how many XPs worth of monsters you need to add to the encounter to keep it at a Medium difficulty).