I have the 3GS since August with unlimited data.
I understand if I keep my current 3GS or if I pre order/upgrade to the iPhone 4, I get to keep unlimited data
But what if I upgrade to the iPhone 4 months down the road or the iPhone 5 years down the road, do I get to keep my unlimited data plan forever?
Or do I have to pre order the iPhone 4 to keep my plan?



I understand if I keep my current 3GS or if I pre order/upgrade to the iPhone 4, I get to keep unlimited data
But what if I upgrade to the iPhone 4 months down the road or the iPhone 5 years down the road, do I get to keep my unlimited data plan forever?
Or do I have to pre order the iPhone 4 to keep my plan?