The link provided describes the BM port forwarding workaround where
there was only one public IP address. May I assume in my case, where I
have several, that the relevance of the TID is to the public IP
dedicated to my A record which now points to GWAVA, and no longer to
GWIA? If so, is that public IP again NATted to GWIA so that IMAP works,
yet the port 25 inbound mail is at the same time port forwarded to the
GWAVA internal address? Finally, how, if at all, does this relate to
the filter exceptions in place opening port 25 to inbound mail to GWAVA?