Ok, so i've been reading about how ATT off-contract phones actually come unlocked, and some people are worry about ATT locking up their phones after they put in an ATT sim. Well my question is, the factory unlock 4s is scheduled to launch anytime this month so if i wait and buy a factory unlock 4s at the apple store, there's no way ATT could lock my phone again correct? I would still be using an ATT sim card, but i will travel and planning to bring my phone with me. 2nd question is, if ATT ask for the IMEI to activate the data, they still can't lock the "factory unlocked" iphone that i'm planning to get at the apple store right? Thanks!