We are going in October and December. Are we able to have fast pass+ scheduled for both trips since they aren't 60 days a part?
I can partly answer this.
On our last split stay (3 nights AoA, 21 nights POR) we had tickets for both stays. This more or less resembles your situation = 2 seperate stays within a 60 days period.
I was not able to book more than 14 days worth of FP+ at the same time.
If I booked 3 days of FP+ for the 1st stay, I would only be able to book 11 days of FP+ for the next stay
The policy seems to be that any guest can only have 14 days worth of FP+ booked simultaneously (APs only get 7 days, DVCs (?) )
So, you'll most probably need to book your December FP+ when you've used up days in october.
If you have 2 stays of 7 days each, you'll be able to book FP+ for the whole duration of your 2 stays
if you stay longer, for example 2 stays of 10 days (20 days total) you'll only be able to pick 14 of those 20 days and book FP+ for those days.
To put it another way, the 14 days counter does not reset with each stay, it's 14 days total over a period of 60 days.
And if you have AP, it will only be 7 days total.