Okay I have chicken eggs in my incubator and it is day 21 for some and 20 for others. I havent heard them pip or roll yet. I candled them last week and there was life. ( I could see veins) but why is it taking so long for them to pip? Other peoples start pipping at day 20! I keep incubator at 100 F but it tends to fluctuate. Please some comfort!