I am on day 21. I have had 5 of 17 hatch already. I have 5 that I really really want to hatch and noticed they are the only ones not pipped yet. They are chirping inside the egg, no pip, will they run out of air if they have not pipped yet? I thought you would only hear the chirp once they pipped the actual shell, not just the membrane inside. Should I give them an air hole or leave well enough alone?