https://bugs.winehq.org/show_bug.cgi?id=57788
--- Comment #7 from Jeremy Newman jnewman@codeweavers.com --- PTR record updated.
dig @ns3.level3.net +noall +answer -x 4.4.81.124 124.81.4.4.in-addr.arpa. 3600 IN PTR mail.winehq.org.
May take a bit to propagate to your local DNS. Google however should pick up on it quickly.
I also updated our SMTP config so our server reports itself as mail.winehq.org not just winehq.org.