Congrats!Yes! But I think much of it has to do with when they hatch. Lucy didn't lay until 31 weeks. Her daughter Rose laid at 26 weeks. While the rest are still a week or two away, Rose's daughter Cream Puff just laid her first egg at 18 weeks yesterday!
wow - that blows the theory away -- And it used to be so predictable. I wonder if as the health and well-being of a breed improves so does the performance. So my next generations of Isbars will not be such small chickens and wait to lay until they are old ladies. I wonder if there is enough early laying to bring the average down?
As you say too,--- hatch time-of-year is an influence. For your three...31+26+18=75 75/3=25-weeks on average; which doesn't quite blow the 24-weeks away, but it is interesting how much you have reduced the POL, to the degree that time of year doesn't have the total influence. And the trend is definitely downward with your flock.