Zimbra import itself when external account has same email?

[bhwong]

We are migrating our email server into zimbra and retain our existing MX record so that Outlook users do not have to amend their POP3.

When we add external account in the user's Zimbra and put our old email server's IP address as it's POP3, Zimbra seems to import itself into itself and ignore the POP3 IP address but using the email domain instead. Can anyone verify this?

Also, is there a way to cancel Get Mail or do we have to wait until it finish downloading 10000 emails?