My AT&T contract says that I am eligible for an upgrade the middle of May, I will be upgrading to the 4G when it comes out. My question is whether or not that means I can cancel my contract then? The reason I ask is that I will be living in Central America from late May to July and would prefer to be down there and not have to pay for the month or worry about roaming charges. Either way, I'll just pull the Sim and leave it here and pick up one there. If I can cancel my account in May and resign in July will I be able to keep my number or will I be issued a new one?