If you are drawing the bow correctly, using your back muscles instead of just hauling back using your arm muscles, it should be okay. If you are just getting started in traditional archery, your draw length may change. Even later on, if you change your form, it may change again. Because of that, I would cut my arrows no shorter than 29 1/2" at this point.
I don't know why it would be longer than your compound draw length. Maybe something to do with the length of your mechanical release or a different anchor.