Need to add a line for my kid. I've got an iPhone 3GS not being used (just upgraded to iPhone 4).
Is it possible to buy say an iPhone 4 32GB white refurb for the additional line, then switch the line to the 3GS and sell the the 32GB white iPhone 4 (They go for about $525+ on Ebay). I know the 4 takes a mini-SIM and the 3GS a standard SIM, so I can't just transfer the SIM. Could I not just tell AT&T we broke the iPhone 4 and need a SIM for a 3GS. I actually have a SIM from the old 3GS sitting around too. Could they not just switch the line to that SIM?
What I'm concerned about is I see on Ebay people advertising 'No Contract' I thought the contract didn't matter, it's the SIM that matters. Or will AT&T not activate a phone with an ESN that was previously tied to a line that is still under contract for another account?