No stupid questions here. We all started out here asking questions. If it's non-medicated starter then you can keep them on it until they lay an egg or around 18-20 weeks. Before that they don't need the extra calcium , it might even damage their kidneys. At the age of laying, their kidneys are mature enough to handle the extra calcium and they need it to form good shells.
I'm thinking that the organic feed is meant for layers and has higher calcium. If that's the case then keep them on non-medicated starter until age of lay. If the organic line has a "grower" formula, minimal calcium, then you could switch at 6-8 weeks of age...and then on to layer pellets with lots of calcium (don't forget to offer oyster shell once they are laying) at 18-20 weeks.
I'm thinking that the organic feed is meant for layers and has higher calcium. If that's the case then keep them on non-medicated starter until age of lay. If the organic line has a "grower" formula, minimal calcium, then you could switch at 6-8 weeks of age...and then on to layer pellets with lots of calcium (don't forget to offer oyster shell once they are laying) at 18-20 weeks.