I know that last year there was no FP for the show. I think that one year Disney tried to get that long SB line under control and gave a pass to the early birds, but I cannot really remember how that worked. I am going in December but not when the traditional heavy hitter narrators are there, so I may just go SB or watch from outside the pavilion. The rest of my family is not really interested enough to use 2 cedits, or pay OOP for this show, I love it though!
If you really want to have a seat, I would check out the menus and prices and book the package. It is a lovely show and it is nice to be able to sit and enjoy it.