Verizon finally works at my home and a place I go in the mountains of Arizona. I've been waiting 4 years for this and now I want to switch carriers because I want the iPhone. How can I do this without jepordizing my existing phone number. For example, if I switch to AT&T and don't like the service, I can return the iPhone within 14 days. However, what happens to my number? Will they switch it back?