15. If, owing to any cause beyond the contractor’s control, or to the contractor taking up the performance of personal dental services in connection with a pilot scheme, the contractor is unable to complete any care and treatment which has been commenced under a continuing care arrangement or a capitation arrangement or treatment on referral, the contractor shall forthwith notify the SDPB in writing of the extent of the care and treatment or treatment on referral provided and of the reason for the contractor’s inability to complete the remainder.