Hello, My four chickens (two Black Australorp's and two Buff Orpington's) are in their 18th week. I am trying to decide when to switch to layer feed. Some people say to wait until the first egg and some say (including the feed company) to start the layer around 16 weeks. Will it harm them much if I make the switch now and they don't start laying for another few weeks? Here are some pictures of the girls. The one Australorp with the really red comb has always had a redder comb than the rest. I was worried that she would be a he. But the feathers on all the birds seem to indicate females. Fingers crossed.