Hi all, I need some help - will try to be clear and brief! I started with a Galaxy S4 (no contract) with AT&T. On pre-order 5s day, I ordered the $199 upgrade 16GB version - my account has not reflected that I have a new contract - as it's not activated. Yesterday, I found a 64GB VZW 5s at the store. I bought it, had AT&T kiosk change my galaxy s4 SIM to a SIM that fits the 5s. We plugged it into the 64GB 5s and all works great - still no new contract. I am not sure I need this much space on a phone. When my 16GB arrives today, can I insert my 64GB SIM into the 16GB phone (BEFORE powering on for the first time)? Will this cause my contract to start? I am not sure what triggers a difference between contract upgrade or no upgrade. Everything is through APPLE - only part where AT&T was involved was at a 3rd party kiosk when swapping my phone # to a sim that fits. Thank you!!!! help greatly appreciated.