2017-08-11 13:47:38 1dfKQf-0005yJ-Ep == me@mydomain.com <root@computer> routing defer (-51): retry time not reached

telnet mail.mydomain.com 25
Trying 11.22.33.44...
Connected to mail.mydomain.com.
Escape character is '^]'.
220 mail.mydomain.com ESMTP Postfix (Ubuntu)
HELO me
250 mail.mydomain.com

exim -bt me@mydomain.com
R: dnslookup for me@mydomain.com
me@mydomain.com
  router = dnslookup, transport = remote_smtp
  host mail.mydomain.com [64:ffff::eeee:dddd] MX=10
  host mail.mydomain.com [11.22.33.44]    MX=10