New email username vs. certificates

DH recently told me to log in for email using my regular email address, rather than my shell user name or old m*** mailbox name. The message also said to use for POP, IMAP, and SMTP access. I would rather use my mail server’s real name,, so that it corresponds with the SSL certificate.

Can I still do that, or is that ability going away soon too?

I’m doing it. I haven’t heard of anything that would stop this. Ultimately, there is a real hostname for your mail server. I say keep doing it until it stops working.