Yes, congratulations. I'm a bit envious -- makes me remember how exciting it was when I was starting out. Enjoy the ride!
More unsolicited advice for you:
-- Go to all the rehearsals you can, even early non-costumed rehearsals. Barbara Morgan, who documented Martha Graham's glory years, said watching how the work changed from rehearsal to rehearsal helped her discover its essence. (Besides, you can get good pictures there; for example, I'm still really happy with
these I shot last week.)
-- Watch classes and shoot pictures of them whenever you can. It's a good way to get a feel for how dancers move. Since classes are somewhat predictable and repeatable, you get plenty of second chances, which helps you be ready when that once-in-a-lifetime shot happens onstage.
-- If you've never done it before, take an adult ballet class. You'll learn useful vocabulary and develop muscle memory that will help you
feel the right timing for a shot.
Did I remember to say have fun? Oh, yeah, have fun!