This guy pipped. But hasn't done the full zip. He just kept trying to push out the same hole. While the shell has several large cracks, he hasn't progressed much since 5-6pm on 6/8. I've read the assisted hatch post. I have one other external pip. How long is too long to wait. He's breathing. He pushes now and again. Not as noisy as last night. But my hatched chick was also cheering him on last night and is now resting.