Received this from mailgun:
"You are receiving this email because we have identified you as a user of Mailgun POP3/IMAP mailboxes. We've previously communicated that we will be disabling all POP3/IMAP mailboxes."
Obviously they (rackspace) can't give away something they would prefer to sell for $5/mo. Has anyone found a similar service that hasn't sold out yet and is not priced per mailbox?