Is it possible to have PS for breakfast in any of the parks before they open? Is there transportation in the morning (early enough) to take you there? Do you just walk up to the gate, show your pass and in you go?
Yes - you can have a PS for breakfast before the park opens. Some folks like this so they can be deep in the park when it does open. There will be no rides open. You need to show your PS info at the gate (or supply your PS number). Not all restaurants are open really early, though, so research your choice or call Disney dining.
There are resort busses that start early for this purpose.
We do this one or two days each trip. For starters, the food is fantastic. And it IS a goal to be deep in the park at open. But also, it's almost worth part of the cost of breakfast to walk some of the park when it's totally empty in the morning. Enjoy!
Last year we had ps for CP, MK at 8.10. We had breakfast over and done with just as the park was opening. It was cool walking down Main Street and getting a picture with castle in the background and no crowds.