For whatever reason, I couldn't preorder on AT&T's site (Premier). It said my plan was not compatible with that phone. Must've been a bug on the site, for kicks I tried adding serveral different phones (including basic phones) to my shopping cart and received the same message.
So I ended up preordering it at Best Buy, and I'm going to pick it up today. It comes with a $10 gift card, so I guess I can't complain too much about not getting the phone a few days early.
Bigger and better each year
AT&T Galaxy S5 (SM-G900A) Rooted!
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