Our RIRs, BSL and Australorp all starting laying around 20 weeks. Although the BSL has had some problems with her egg shells being too thin. After I changed their feed and added egg shell to the oyster shell feeder she has been doing much better.RRI and Barred Rocks, You are prob right, I was just guesstimating about what I read online, some reason I got 19 weeks stuck in my head....So maybe December eggs? LOL