I am hoping to join you all!
My black copper marans started going broody a week or so. She started right about the time I integrated my 4 month old cockerel to the group. I have no idea if the eggs are fertile yet or not, but I gave her 7 eggs yesterday (7/18). Then, last night, I realized I was short an egg for a cheesecake and took one back (it'd just been laid that day, so I think it was fine to eat). I think I saw that bullseye that's supposed to be visible in fertile eggs.
So, she has 6 eggs to sit on. I marked them all with a marker because she is in the favored nesting box and the other hens keep sneaking in there and laying eggs too.
Anyway, I figure next week I'll candle them to see if they are possibly developing chicks.
I think it'll be really exciting if it works out. The cockerel is a black copper marans. There's 1 BCM egg, 1 white leghorn(ish) egg, and 4 EE eggs (two of which are fairly olive to start with).