Sort of.
You can enter the park with a party ticket at 4:00.
You can also book FP with a party ticket up till 7:00 (or I think they changed it to the last one needs to end by 6:30.
But point is, you don't need a park ticket also, to book FP.
At least you did not last December.
I bought DD a 7 day ticket and 1 day party ticket.
We booked 8 days of FP
Also, you should not need FPs for the Christmas party as ride lines are traditionally short (maybe not 7DMT). Most things will be walk on as people spend their time on the exclusive party events instead of rides.
Yes.
I wouldn't book any after 6p
While they should be allowed, there seemed to be reports of MDE auto-cancelling some late FP+ on party nights, and then you get the hassle of fighting IT for your FP+