What does it mean to be a Backup?

If you received notification that you were added as a Backup for an Op, the business designated you as one of the standout bids that they were not able to select. If one of the Operators that they selected for the Op withdraws, you will receive a notification that a spot for that Op has opened up. This notification is sent out to all Operators that were designated as backups at the same time, and the first Operator to respond by clicking the "I'm Interested" button through the notification will win the bid.