I believe production reds are hens bred exclusively to lay lots of eggs, it depends on the hatchery what breeds for into them.
I am horrible at guessing red chickens because they all look the same to me!
For yellow-legged chickens, the longer they lay eggs, the more pale the legs get. So these could be hens that have been laying for a while.
(The yellow pigment gets moved into egg yolks and out of their legs and beak and some other places. It starts to come back if they take a break from laying. This doesn't hurt the chicken, but does provide a handy way to see which hens have laid more eggs than others. It only happens with yellow-skinned chickens. The ones with white skin still lay eggs with yellow yolks, but never have the yellow move in or out of their skin.)