We have one day at Universal IOA, I think we are going on a Thursday at the beginning of October. We are not staying on-site, so we don't have early entry. My son is a Harry Potter fanatic. He is 9 and has read all of the books. We are staying at Disney and this side trip is a surprise for him. I want to eat at Mythos (he is also really into Greek mythology). This will be our only meal other than snacks. When is the best time to make our reservation, so we maximize our time at the park? Thanks!!