As it should be. EE are not a breed so there are no standards. We can't even agree on what a good definition of an EE is. An EE can lay any color of egg, have any kind of comb, have any color of legs or earlobes, be any size or any color. If somebody tells you that their EE did something that's like someone telling you that their dog did something but you don't know what breed their dog is. An EE is a chicken, nothing more.
When they do. Some people have seen a chick just a few weeks old try to crow. I've had several cockerels that did not try to crow before 5 months when I ate them. If you have a few cockerels the dominant ones may keep the others from crowing but even the dominant ones don't always start to crow until they are petty old.
Substitute the work "chicken" for "EE" here. Some chickens mature early, some mature late.
When they do. I've had EE lay their first egg at 18 weeks. I've had some wait until 9 months to start laying.
At 16 weeks old we can maybe tell you which are males or females if you can post photos. For each chicken in question a closeup showing the comb and wattles are really helpful. A second photo showing the legs, posture, and conformation can be really helpful.
For fun I'll show some of my EE. You may not be able to tell it but they have different kinds of combs and different colors of legs and earlobes. They all laid blue or green eggs.
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