Chickens are 16 Weeks Old - Nest Boxes? Lay with day length?

[aart]

None of my chickens have bright red combs yet.

Just leave them blocked while you are gone.
Deal with it when you get back.

 

[andreanar]

Most of my chickens don't lay until late. None before 24 weeks. But I keep slow maturing breeds like brahma. If you keep production breeds, its possible for them to lay now, but I wouldn't worry about the nests until you get back in any case.