Would the rail link open before the first houses are built?

We are currently in discussions with Network Rail regarding the provision of a new station at Sharpness and the provision of passengers services to Cam & Dursley on the existing railway. The intention is that if the rail link is not open before the first houses are built an express coach service will be provided from the outset so that new residents can rely on this from the first day they move in without the need to rely on cars.