I made some major changes in the last 2 months: expanded some pens, added 2 more, got bigger coops, replaced some older hens with younger ones, and replaced some roosters. I know chickens are creatures of habits and don't do well with changes and stress. In one pen, they are not molting, but they quit laying 100% and haven't laid anything for one month now. Is that normal? How long does it take for them to start laying again? Any tips on how to help them go back to normal? Thanks!