My girls are only 5 weeks old right now, and still prefer to sleep in a warm pile of chickens. I've not bothered to block off the nest boxes. I have two boxes, built inside the coop. My girls do enjoy sleeping ON the nest boxes, rather than IN them or on the roost. I figure this good enough, they still get to cuddle, but the are choosing to sleep up off the floor, which is ALMOST roosting. And every morning when I come out to check on them, they are all perched on the roost waiting for me.
Unless they change their habits and start pooping in the nests, I won't worry about it. I would suggest you do the same. If your boxes are open, leave them that way unless your chickens start sleeping in there. If your boxes are closed, don't worry about it, open them up a few weeks before you expect them to lay.
Unless they change their habits and start pooping in the nests, I won't worry about it. I would suggest you do the same. If your boxes are open, leave them that way unless your chickens start sleeping in there. If your boxes are closed, don't worry about it, open them up a few weeks before you expect them to lay.