Kickstarter copies will shipped out in May, and perhaps earlier. Then to select stores after that. Many copies will be held for future KS pledge levels as well.
The likelihood of a quick turn around is one of the main reasons I backed (along with U.S. production and a fun looking game). As long as you are close to your time frame, I would gladly back your games in the future (assuming they also look like fun games). Any company that has shown they cant or likely wont come close to their estimates, I wont even consider backing anymore.