Last fall we set things up so that email@example.com was listened for at uvic and forwarded to firstname.lastname@example.org. When I got back after Christmas and tried to email admin@canadianmysteries, I got a message from canadianmysteries.org reporting no associated email accounts.
Not sure why megamailservers is still listening for canadianmysteries.ca (dns reports primary servers are the uvic ones), but assuming they get the email, they correctly report no email accounts, because we killed the email accounts to ensure nothing went to them).
Turns out that there are two separate configurations, one for mail sent from on-campus (I'm not sure if that means geographically or from a *@uvic.ca account) and another for all other email. Somewhere over the Christmas break the first of those two (i.e. internal source) must have been modified with the result that mail from my account to email@example.com wound up at canadianmysteries.org .
Sys-admins updated their config files and everything seems to be working now.