They are going great rexy. I have forgotten how to sex them I think. Is it black wing tips on the males? If that is the case I have a lot of females but we will see in a few weeks.
You will be able to tell by the comb by 3 weeks. There is an odd BTB coloured male in there, so that throws it off a bit. The boys will have black, and the girls have brown wings by about 2 weeks. In my line the girls nearly always feather faster, both tails and wings.