They are considered point of lay by 20 weeks of age. My hens also lay there first couple of eggs outside (they are free-range in a large 10 x 20m camp with an open coop) - until they realised that they have wonderful little nests inside the coop. Mine taught themselves so to speak. As for what TIME they lay eggs, it differs from hen to hen. My Orpingtons and Ovambos are usually the early birds and I'd have at least one egg by 6:30. The leghorns and Potch Koekoes are a bit lazier and would lay late morning and brood on them until noon. It is also weather dependant and I've noticed my hens lay less eggs and a bit later now that it is winter in our part of the world.