Last time i get an an at&t phone.. rllyHello there. Questions belong in the "question and answer" section. Not the general section.
I wouldn't hold your breath for an unlocked bootloader. It's probably not going to happen for a long time. The S4 is still locked and it's a much older device. Once it becomes outdated and unsupported hopefully it will be unlocked. But I'm betting I'll be on a note 4 by then.