I'm assuming that you are looking to be in the front of the group, for park opening. If that's the case, you might want to be at the bus stop earlier than 8:15....I've gotten to AK at 8:30 for a 9:00 opening and been at the end of a huge line...took about 15 minutes to get to the gates. I would plan on being on the bus by 7:45, and at AK by 8 or so. But, that's just my experience. I don't think there will be any other stops....YC/BC usually share the morning bus, while BW and S/D share their early a.m. bus. The only stop you may make is at BB, but I don't know how early they start stopping there.