When you make your fastpasses, you may want to consider whether your plans will change if Pandora is open. Maybe make 2 and see how they differ.
The problem will come deciding whether to save a fastpass in case they open up, or make 3 and be prepared to drop 1 for a Pandora ride. It think there are 2 new rides coming, don't know if both are expected to have fastpass. There's also Rivers of Light to consider.
I would think fastpasses will only open when they are absolutely 100% sure of the opening date, probably a week or so before, especially after the whole ROL fiasco. They might even open and then introduce fastpasses. So at 60 days I would make 3 based on what's there now, then either allow an extra day or half day for Pandora & ROL, if these are really important to you, or decide which rides are most important to you and change the fastpasses accordingly.
At the moment it's a guessing game!