If it's Islands, there will be more people there earlier than if it was Studios, due to Hagrid's and Velocicoaster. I would aim to be at the park gate by 6:30am at the latest. Remember the wait to checkin at the hotel and the time it takes to walk/take a boat over. It also depends if you are trying to do both rides during EE. You could probably show up a little closer to 7am, maybe 6:45am, and still not have a big wait for 1 of them. If you are not riding either of these, then I wouldn't worry when you get there, just use Express Pass then.