The Rebel Legion has written in with an update on what they'll be offering attendees during Celebration VI:
We’ll be doing our Diplomatic Mission game again, where participants get to help us keep the Death Star plans from Imperial hands. Game badges can be picked up at the Rebel Legion booth on Friday (while supplies last). Then on Saturday, participants will collect all four pieces of the Death Star plans (they’re stickers) from our costumed secret agents; and Sunday, see if they've won any raffle prizes. It’s free and everyone that plays gets a surprise!
Look for the Rebel Legion booth near the Droid & Shoot A Trooper area in the main exhibit hall.