I dont think that should be a problem. Class reworks normally come with every expacs. They just need to put in way more effort then before to meet the expectations of their consumers and the product they are deploying. No more half doing the work required. SL was in beta for almost All it’s release with how poorly it was executed.
Summary: they can easily so both, new class and full rework.
This link is a post I made about wanting them to focus on class design and reworks for new expac