On which molt do barnevelders get their sex related breast feathers?

[MarGray]

I know future roos will have blue/black breast feathers but unsure of when it shows?
I hatched 4 blue laced barnevelder eggs about 5 weeks ago and I'm incredibly impatient.

 

[NatJ]

I don't have experience with Barnevelders specifically, but with some other similarly-colored breeds I have sometimes been able to sex chicks by the color of the first breast feathers they grow. At other times, the first breast feathers were confusing (not obviously male-colored or female-colored, but sort of a mix), but the next molt was clear (although I usually knew the sex by comb size & color before that next molt happened.)