Inbound mail to your Route64 addresses now works on ports 25 / 2525 (and 465 / 587)

Inbound mail to customer networks is no longer blocked. You can now receive mail on your Route64 addresses on TCP 25 and 2525; on IPv6 tunnelbroker ranges inbound 465 and 587 are open as well, matching IPv4.

Outbound is unchanged: direct outbound SMTP on port 25 stays blocked from all r64 IPs, and submission on 587 / 465 / 2525 is still limited to the major mailbox providers and relay services listed in our earlier announcement.