Seriously. You need to get this together. You are about to release a major thing to the world and you're telling me that when someone change their e-mail address everything on their Oculus Home account have to go because they need to create a new account?
Good to know we have Steam where an e-mail change is possible - and when I think about it, any other account I have.
Sorry. The system wasn't designed to support this, though it's understandably a legitimate request. It is something that may be added later down the road, but probably not in the immediate future.