It does seem to me that this is a situation in which there could have been data corruption on Bitwarden’s end (which should qualify you for a PITR restore).
The evidence for this is the fact that you did not change your master password when changing your email, the fact that you use(d) your master password daily (making a memory failure unlikely), and that the new email address appears to be correctly captured in the server database.
@dwbit Are you able to intervene on behalf of OP?