When I went in the Navy(many, many years ago) no matter what pay grade you are promised, everyone is a E1 through boot camp, everyone. You don't get the paygrade until you finish boot camp. Also if you do good in boot camp, don't get any marks on your Hard card(what they called it back then) the CC can reconmend you for automatic advancement to E2.
I chose a school that got me E2 out of boot camp and E4 when I finished the school.
Where are they sending you for Boot camp?