This feature is best used for the following:
- If you will be online and available to help if the session doesn't fill up
- If you are willing to help but don't want to take a spot for someone that needs or wants to attend the session
- You are willing to join if someone doesn't show up
From the Web:
- To join a game session as a reserve, simply navigate to the game session you would like to be a reserve in. Then click join and then click join as a reserve.
From the App:
- Long press on the join button: