Phil, i'm an insane fan of you. I've watched almost all of your playthroughs.
I'm a big fan of the Kingdom Hearts series, so i can't wait for your awesome KH3 playthrough.
However... Phil, before playing KH3, YOU NEED TO PLAY Birth By Sleep and Dream Drop Distance.
If you don't play those two games, you're not going to understand anything about the plot of KH3.
This is not like KH2, where you can skip Chain of Memories, and the only thing you will not understand is the Roxas prologue.
If you don't play Birth By Sleep and Dream Drop Distance... You're going to understand absolutely nothing in KH3.
It's very likely that KH3 will come out this Christmas... Maybe you could do a summer play through of BBS and DDD?
Hope you actually get around to playing those games, they are pretty fun actually.