Hi Tim! Welcome to planDisney.
Gawrsh! I am sorry you missed out on the all-new out-of-this-world attraction,
Guardians of the Galaxy: Cosmic Rewind. Currently, there are a couple of ways to experience this reverse-launch family-friendly roller coaster. Let me walk you through the process.
First things first, you must have both a valid
Theme Park Ticket and
Disney Park Pass Reservation to
EPCOT. Got those? Great! For the complimentary option, try joining the
virtual queue which opens up promptly at 7:00 AM through the
My Disney Experience Mobile App. Before 7:00 AM, open the app, and click on the three horizontal lines in the bottom right-hand corner. Next, select "Virtual Queues." You can choose "Join a Virtual Queue" and select your eligible party. Precisely at 7:00 AM refresh the app and confirm your selection. If the stars lined up correctly, you will be issued that "boarding group" you are referring to in your question. The app will update throughout the day on which groups are currently boarding and send you a notification when your group is called. Also, if you did not get assigned a group in the morning, you can try again from inside EPCOT at 1:00 PM.
Alternatively, you can opt to purchase an
Individual Lightning Lane through the app. Tap on "Tip Board," select EPCOT as your park, and scroll down to Guardians of the Galaxy: Cosmic Rewind. If spots are open, tap on the Individual Lightning Lane icon to choose a time and submit payment.
I am also linking you
six easy-to-follow videos explaining different aspects of
Disney Genie Service for your convenience. I recommend you get familiar with this service and the mobile app before your theme park visits.
Keeping it Magical,
Cindy