I have a very diverse flock but keep tract of my lines. Some birds of the same line even slow at different rates.
G001, B002, and B003 are my prime examples as they are all directly related (linebred sisters). They never have light supplement. I have, however, upped their vitamins and minerals since I don't trust TSC's grain to be "fresh". Since doing that I have gotten more eggs out of the old gals but nothing else is different in their routine.
"G1" aka Gin, is pretty much as slow as it can go for a weekly egg rate, at 1 a week if I am lucky. Maybe 2 during good weather/seasonal. She is 6 years old.
"B2" Agnus, is the same as Gin. She is about 5.5 years old.
"B3" Berdeth however is 8 years old and giving 3+ eggs a week, sometimes daily during spring/summer. She is 8 years old. Now, I'd consider that unusual, but taken that opportunity to breed her and her lines to get that longevity. The first hens showed good promise at laying near daily or taking after G1 and B2 and being heavy seasonal layers. Berdeth shows no signs of slowing down. In fact I got one of the biggest eggs she has laid today.
I've retained some of B3's chicks to see if they have the same life span of laying. The problem is, of course, it will take me 8 years to find out!
If it matters, these birds lay a Medium size egg.
The other lines are EE lines. They are coming 3 and are seasonally heavy layers (daily) and stop all together in the winter except perhaps 1 or 2 a month. They lay very large eggs and are large enough that I would consider them dual purpose. I expect them to lay well at least until 5 or 6 years old.
Ok, I don't know who is laying what. I see a hen or two in the nest box here and there but not all the time. Do you have a camera on the nest boxes or what ? How do you know ?