This has been an on-going issue in our community for years. If a user attempts to change their email address it will work until they log out of the platform. We even had difficulty when attempting to change employee emails for a recent SSO project. I am afraid this may not just be an issue in this community but many Khoros communities. Luckily we have eliminated the ability for our customers to change their own forum email address as we have now tied to their internal accounts, but it is still happening. Just thought I would share.