I've got 18 that were fertile and developing at the 7 day mark in the first batch, haven't candled since, they hatch Friday/Saturday. Air cells are weird but I've been told that's normal with shipped eggs. Have a smaller batch (8 fertile if I remember right at the 7 day mark) due the following week.
Had 7/10 local eggs hatch this past week from a mixed dozen that I bought. 4 Silver Penciled Rocks 2 mystery eggs that were marked BC and turned out to be Black Cochin and one mystery chick from an unlabeled egg that looks like either a buff or white wyandotte. Some poultry god somewhere really wants me to raise Cochins, it's NOT happening. Just saying that because I bought those 6 chicks from 4-H group that were supposed to be White Langshans, they were White Cochins, now mystery eggs end up being Cochins...not...happening.
How are your chicks doing? I still have not found a genetic explination for how a blue baby can come from all black parents. stumped but awesome.