I have Postfix setup to automatically forward any mail that goes to root to an external address. I just recently changed my email main email address from a Tutanota one to a Mailbox.org one. I went into /etc/aliases and switched out my addresses there, so now it looks like this:
> # See man 5 aliases for format > postmaster: cassidy > > cassidy: poperi...@mailbox.org > root: poperi...@mailbox.org > clamav: root After I did this, I forgot that I had to reload Postfix, so it was still sending mail to my Tutanota account. When I remembered, I did "sudo service postfix restart". Now mail isn't being forwarded to either addresses.