no i dont think there'd be any difference either way you went i keep mine just on flockraiser/all flock from the get go and just add free choice oyster for my girls that are laying and they've done great and its simple then having to switch between three feeds and with feeding flockraiser i can just add my young girls to my older ones after introducing them and not having to worry about the excess calcium thats in the layer as flockraiser just has a little and the oyster shell is in a seperate feeder and the young girls wont mess with it since their bodies dont need it.