Hey guys, I had an old iPhone 5s that has my current service attached to it. When I got my new iPhone 6, I simply put the old SIM in the new phone. As soon as I did, I got a text message from AT&T saying: "Your new device requires a new SIM card to give you access to all services. Please visit your local ATT store to get a new SIM." Do I really need to do that? I called my own number and it seems to be working fine. Data seems to be coming through as well.