I agree We did the math and added the time and are about 15 weeks! These seem to be more mature than our other ones we got last year. Those were 2 roosters and 2 hens. Both roosters were rehomed and only one hen survived.
According to our local feed store this is normal. They are exactly 12 weeks old from hatching from our family farm. NOT my farm but my uncles. I was there when they hatched.
The middle one was laid yesterday from one of our 4 11 week old chickens. The right one laid from another 11 week old chicken. The far left is from our one and a half year old chicken.
I called our local feed store and they said it is possible for an 11 week old chicken to start laying.
I have 4 almost 12 week old chickens this is my second batch of chickens they are all the same age as from hatched in late March. 2 of them are laying eggs already.