I candled, I didn't see an internal pip. There's more empty space in the egg now than just the air sac. It used to be fully dark except for the air sac. Not sure what that means? Thanks for the help!
So we had a batch of 6 eggs in the incubator. They were calculated out to hatch either Friday or Saturday (I can't figure out what constitutes day 1 lol). However, five of them hatched a day early on Thursday, and one egg is still unhatched, not pipped, etc. on Sunday.
I had candled them all...