They cannot win the X Prize until they have carried three people twice. The flight on the 21st is only planned to have a pilot - no passengers.
They don't have to carry three people. The vehicle must be capable of taking three people, but they can take ballast instead and still win the prize. This flight will not be a prize flight, because they haven't provided adequate pre-notification, but if it's successful, I would expect a prize attempt during the summer (perhaps with a first flight on July 20?).