The dreaded split between UPMC and Highmark has been delayed. Highmark customers, who would have been forced to give up their UPMC doctors by mid-2013, can relax a little. Their access to UPMC services and physicians is now guaranteed through 2014. The question is, what happens in 2015? This health care dance feels a little bit like the doomsday forecasters who keep moving the date of the end of the world.