Bellsouth email access problem

I run a hosting service for country clubs and golf associations. Two of my clients in Alabama (Hoover and Fairhope) are having issues with their members with bellsouth.net email accounts. Since December 2017, those folks are not getting the emails they requested. Our IP is not on any blacklist, and we do not get any delivery failure messages. Our email logs show that the emails leave our server, and are accepted by the receiving servers (no error messages in the logs).

Our clients are frustrated, and we have been through all the AT&T hoops when we changed servers/IP addresses over 3 years ago. All of our PTR and other configurations (rDNS, DKIM) are solid, as everything was working up until a month or so ago.

Folks in other geographic areas are not reporting similar issues (Florida, Georgia) with far more email accounts in play. In the past, we've been told that this is not uncommon in AT&T as the acquisition of markets means legacy systems can be left in place.

If someone could give me direction, an email address, or a way for my clients to contact someone who can troubleshoot their email accounts (from the server side, not the client side), we'd all be grateful.

Rob Bristow
Chief Technology Officer
Classic Club Solutions, LLC
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