I purchased an iPhone 6s using an upgrade from my Next program on launch day. I enjoy it but coming from the iPhone 6 I want to try the 6s+. Of course none of the AT&T stores have a 6s+ in stock. I was lucky enough today to reserve a Plus at an apple store. So my question is can I return my 6s at the AT&T store and head over to Apple to purchase the Plus? I've been getting different information all day so if anyone has any experience it will be helpful. Thanks.