I agree, you get Express Pass both days. However, you have to check in first. Since the parks open at 9:00 AM (or earlier for early admission) but the rooms are not ready until after 3 PM, the usually means going to the front desk twice, once to pick up your Express Pass, and a second time for your room key. (They might have some automatic way of doing this but if they do, I'm not familiar with it.)