The more we talk about this, the more confused I become.

I used tcpdump on ports 25, 465 and 587 to monitor an outbound email to my ntelos/lumos address. The send went out through port 587, not 465 or 25, on my system. So the changes I made to postfix's main.cf file have routed emails to my outbound smtp provider, which is smtp2go, via that port. They are being received at smtp2go without issue. Yes, it is an outbound server that I have used for a number of years when I could not get SMTP to function on ntelos/lumos.

However, when I look at the emails directed to my domain name, www.wa4rts.net, smtp2go indicates that it is trying to route them to the correct domain address resolved by dns but the connection to my domain times out. Since you are saying that all incoming emails are routed through port 25 and comcast blocks port 25, therein lies the problem.

I can only assume that ntelos/lumos does NOT block port 25, but since that service is still out for me, I can't confirm it until it returns. So the problem remains -- if the comcast connection times out, routing email to the backup at ClearOS, and that backup restores via port 25, how do I deal with this problem.

I apologize for being somewhat dense, but it just doesn't make sense. Sorry to waste so much of your time and draw on your good nature.