So this is what I have with Verizon: iPhone 5 with 4GB of data plan. (eligible for upgrade) iPhone 4S with unlimited data plan. (not eligible for upgrade) Basic phone no data plan. (eligible for upgrade) All phones share 2000 minutes. I have heard others speak about using the basic phone as a proxy to get new phones onto the unlimited data line. But cant I upgrade on the 4GB line and just switch that phone to my unlimited line too?