I had a question about the porting/sim cards. I preordered a 16 gb I4. My contract with VZ ends on the 9th of July and will port the # over after. After ordering the 16 GB I immediately regret not getting the 32 and my gf has been so kind to use her upgrade at the end of the month to get a 32 gb. My question is all I have to do is slip in the sim card and I'm good to go or do I need to call AT&T?