User blog comment:Cogitoergosum/Question.../@comment-961279-20100809135101

It's between 8-9 months from initial idea to finished 30-minute episode. It's in one of the interviews of Dan and Swampy, I think. A special would take longer than that.

Neither one includes any delay that might come from Disney in when they decide to broadcast the episode. "Undercover Carl" was first revealed in a March 2009 article on MSN and they had already started on the storyboard, so they would have been at least a few weeks into making the episode. Disney didn't air that episode until January 2010 in Latin America and Feb/March for Disney XD/Disney Channel US.