I personally think youll be just fine arriving at 9:30 rather than 8:00. DH and I arrived after 9 and encountered no check-in lines (just few people in front of us), no issues finding spots under umbrellas. Our dolphin swim was around noon, but we wouldnt have cared if it were a later swim time. Dining area was nice and quiet by then as well. In fact, waking up early to make it to parks commando style is no vacation to us, so we purposefully avoided 8am arrival. To summarize, yes, I believe youll be just fine arriving by 9:30 and will still have plenty of time to experience every aspect of the park.