I suspect that I need to check for hidden nests that some have made to lay in while free ranging rather than returning to their nest box. A sudden drop of around 14 eggs a day is not normal when their have been no major changes in feed and their environment.
Its been 11 or 12 eggs a day out of my 14 all month. If i have had 10 one day it was 13 the next so its been more 12 a day than 11. I'm getting a double yoke about twice a week, that might be why 11 and not 12.