Thanks for the explanation on dating the eggs! GardeNerd had explained it to me before but I couldn't remember exactly. I was going by basically what you said.
I have 5 fluffy little cuties in the incubator now. 3/8 not pipped. Based on my prior experience with hatching, I would say these late guys are not going to hatch (altho I'll give them more time for sure). Wish I understood what was happening there.
I couldn't sleep last night so I got up to check the bator & ended up spending 2 hours there watching. Yikes, I'm tired!! One of the eggs was zipped all around but took 2 hrs to get out of the shell! The membrane was still attached in several places, and it looked in this case that being vertical was making it harder for the chick to get out. I was worried that it would dry out & get stuck, but no. I could have helped it by poking a wire through the vent hole, but I really wanted to know whether it could make it on its own.
I would post a picture but probably more responsible to get myself going!