If treated like crafting were it playing catch up I can see it work that way new content would be locked for customization builds whatever that entails. The older content is unlocked after newer content is released or couple patch afterwards. We already have rules in duty finder now were we can enter uncapped and do older content already breaking the balance anyways, can have rules set in place were new content keeps it balance currently or players first time running content it locked until you've completed to unlock it or not. /shrug just my opinion at least giving an option how to treat it I'm sure people will disagree with method of course