Some chickens take longer to lay eggs than others. They definitely will lay eggs. I know it is very hard to wait until that first egg. I would put some golf balls in the nest box it signals to the pullets where the choice place to lay an egg is located. They don't know the difference between a golf ball or an egg. I would put out some oyster shell too, they may peck at it a little but it could be an indicator that they are ready to lay. You will notice too that the combs will become really bright cherry red when they ovulate so it their combs are pinkish or dull red they are not ready but look at them in the mornings and if you see that bright vivid color you will know for sure.
Caroline
Caroline