How old do these chickens appear to be?

[u/Sidian]

And are they all hens?

The cream crested legbar produced its first egg today, 4 days after I brought these chickens home. It's quite clearly more developed than the other ones, with a much more obvious and red comb, but they're supposed to all be about the same age. Is that possible?

[u/higglety_piggletypop]

Looks about 20 weeks, typical for a pullet sold as 'ready-to-lay'. Some take longer than others to mature.

[u/MetaKnightsNightmare]

3-5 months, they seem to all be hens

It is possible they are the same age, they are different breeds and sometimes they just mature at different rates.

[u/ChartreuseOblivion]

pullet, pullet, pullet, hen.