Feature Request: Display email vs Login email

We have some users who have signed up for BLOX with their personal email address, but have since gone on to be staff (from volunteers) so they then get their own site-branded email.

We are unable to change their email address since the system spits out that they need a static address for login purposes. We could make an entirely new user account, but there's too many articles to change over.

It would be great to be able to add/change the profile "display" email address to be different than the login one, so emails can go to a work address rather than a personal one.