This is really a minor issue, just want to leave it for you to make things consistent at some point.

Previously it was possible to specify relay as address only (IP address or relay.example.com), and if no port was specified it would default to 9009.

Now it fails with an error "bad relay address" if you don't specify the port, so the fallback to 9009 no longer works.

I leave it up to you to decide what is better, require port (and remove fallback) or allow specifying relay address without port.