I have a Buff Orpington setting on 9 eggs right now in Northern Wisconsin. It's still really cold and this is my first time hatching eggs at all. They were laid on 2/27 and put under her that same day. There were origionally 11 eggs. After 8 days, I candled them. There were two eggs with nothing in them, so they were removed, one that I could not tell because I can't see through the shell, and 8 eggs with about one-third of the egg dark. I then candled them again last night (at 15 days), I can see that those 8 have grown to take up most of the inside of the eggs with a air pocket at the top of each of those eggs. There's still the one that I can't tell because it's a Aracauna egg and it's green and too dark, so it's still there also. It's going to be so cool to see these litte ones hatch on the first day of Spring or the day after. My hen is in a brooding pen inside the coop, I do heat the coop at night with a small barn heater, but not during the day. I'm not sure if I should put a heat lamp above the brooding pen or not. I see people say that Mama hen can take care of them, but I too worry about the cold. Now I wait. Do they ever hatch earlier than 21 days? How long should I wait until I discard the eggs? Very excited, but a little nervous also. Wish us luck!