Tailspinner, Welcome. Read about Elkhorn and Noboru from party 2 in the RG thread (it's pointed to in the first thread of all the threads but itself). Pick one you would like to play and you can jump in. A combat is starting in party 2 so catch up as well as you can. If you pick Noboru, you can just say you were following the party and finally caught up to them after a wrong turn.
Fitz, I'm curious how the group with less intel goes about the dungeon compared to the group who a goblin in it. When we finish adventure 1, we can discuss mixing and matching and even running parts 2 and 3 simultaneously with separate groups.
As for the rules update, I'll decide when I see them. For now though, my thoughts are stick to the original rules for adventure 1 at a minimum. But that will depend on how the new rules are presented.