We have a pretty large music festival we have been requested to live broadcast from in a couple weekends.  My question is if there's an easy way to intermittently go live without interrupting AutoDJ?

If you're using Shoutcast v2 or Icecast (i.e. not Shoutcast v1) then you can use DJ accounts for this purpose:
http://www.centova.com/doc/cast/user_manual/02_reference_manual/05_DJ_Management

When using DJ accounts for live broadcats, the autodj will go silent, in the background, resuming when the DJ stops his live stream.

Yeah that's what we were planning to do.. I just wish there was a way to do it where it would sync in between the AutoDJ playlist, like if it uploaded on the fly to the "instant" playlist.