Oh Omak Dave, there is another issue to consider also:
hens can store viable sperm for up to 2 weeks.
It is thought that this ensures she be able to lay a clutch of eggs (and hatch them) if the cock bird was killed, as they often are, by predators.
A flock left without a male, would still lay fertile eggs for up to 2 weeks, ensuring the hens hatch more males (and females) to carry on.
So even if it got really cold, (freezing or below) the cock would go sterile, yet the hens still lay fertile eggs for up to 2 weeks.
Cool, huh ?
Mother Nature is amazing !