It proved not to be complex, just a matter of the current config grammar. Even with the old versions you can set the port to `0` and then it should not appear in the headers.
Anyhow, I pushed also a commit that allows advertise with host only, being an alias to `... advertise host:0`. When listing the sockets via rpc, the port 0 will appear, but in headers should be no port.
I did basic testing, if it does not work, reopen this issue.