One chick hatched in nothing flat this morning. Pipped yesterday around 8 pm and this morning at 7 am it zipped and hatched within 30 minutes. One pipped at 3pm yesterday and 22 hours later it zipped 3/4 of the way but the whole egg was turning with it. I thought it was probable stuck and kept pushing for over four hours before I helped a little bit and it popped out. The membrane was tough. Now I have others that have been pipped for at least 24 hours and nothing more happening. Temps are 99.3-100.5 and humidity runs between 65-69%. Should I be worrying yet???