Submitting this as a NEW answer, since it clearly contradicts the first, based on information just received - after an additional 2 years.
According to information just released today, August 6, 2015, Prison Break will be back! for a season of 10 further episodes.
From PopSugar:
Cochairman Dana Walden added that the reboot will be "a bit of a sequel" that picks up with the characters several years after the events of the final season of the show. "It will address some questions that were set up at the end of the series," she said, and though she didn't confirm who besides Purcell and Miller would be back, she teased that "some of the iconic characters from that show will be back." Though there's no word on when it will come back, we do know the return is slated to be a 10-episode arc.
Cochairman Dana Walden added that the reboot will be "a bit of a sequel" that picks up with the characters several years after the events of the final season of the show. "It will address some questions that were set up at the end of the series," she said, and though she didn't confirm who besides Purcell and Miller would be back, she teased that "some of the iconic characters from that show will be back." Though there's no word on when it will come back, we do know the return is slated to be a 10-episode arc.
