I don't have that long an experience with chickens, but I can certainly say that they DO allow breeding before they are laying.
With the ducks it was easier to tell. They were breeding often every day for over a month before they started laying.
I do notice that, generally speaking, it is the earlier-maturing (and those expected to lay soonest) that the cockerels breed soonest. (My red sex-links are bald at the backs of their heads now!) Many of my pullets still don't allow them to breed at all. However, the banty pullets are allowing them to breed, and I don't expect eggs from them until after all the other breeds have started.
FWIW,
trish