Hi Nancy! Magic Kingdom will actually open early for guests who have a reservation in the park for breakfast and/or a visit to
Bibbidi Bobbidi Boutique. Check with your concierge desk the night before your reservation and they can tell you what time to be ready for the early bus that can bring you to Magic Kingdom. If you are staying at a resort on the monorail, the monorail will be able to bring you to Magic Kingdom in time for your reservation.
As far as your PhotoPass question, you can obtain a PhotoPass card from any PhotoPass photographer so you do not need to wait for anything to arrive. If you are using PhotoPass+, you will need to redeem your voucher prior to using it for attractions or dining locations. Here is a list of places you can redeem your voucher:
Magic Kingdom - Exposition Hall
Epcot - Camera Center
Hollywood Studios - Cover Story
Animal Kingdom - Garden Gate Gifts
Downtown Disney - Marketplace (inside Guest Relations) and Team Mickey
M.Mouse Mercantile at Disney's Grand Floridian Resort & Spa
Trader Jack's at Disney's Polynesian Resort
Zawadi at Disney's Animal Kingdom Lodge
Beach Club Marketplace at Disney's Yacht & Beach Club Resort
Have a magical vacation, Nancy!