A:AnswerThey have different options now where you don't have 2yr contracts. It's called next where you buy the phone for about the same as it would be with a contract but you're not obligated 2 your carrier you're only obligated to pay for the phone.
A:AnswerFor me, they sent an email when to pick it up. They normally hold the pre-order for 72 hours from email receipt. Once that expires, the pre-order goes to the next available person.
A:AnswerYes - as long as you are using an at&t SIM. S6 can also be SIM unlocked (either through at&t - for which they will typically ask you to maintain a subscription for period of time (usually not more than 60 days) - or through an online service for $10-$20).