Thanks.
Yeah this does look like it. All the normal handling is done in the ua->loop unless you want to write your own.

On further inspection, the callback I need (ability to read a 302 response), does not exist.

I went ahead and added my own callback mechanism in NET::SIP::Leg to hit a cb_recieve callback if it's defined

Now I can read all responses via callback, even the ones that Net::SIP doesn't handle