s 61D Effect of revision or revocation of development order on incomplete development
(1) A development order or local development order may include provision permitting the completion of development if — (a) planning permission is granted by the order in respect of the development, and (b) the planning permission is withdrawn at a time after the development is started but before it is completed. (2) Planning permission granted by a development order is withdrawn— (a) if the order is revoked; (b) if the order is amended so that it ceases to grant planning permission in respect of the development or materially changes any condition or limitation to which the grant of permission is subject; (c) by the issue of a direction under powers conferred by the order. (3) Planning permission granted by a local development order is withdrawn— (a) if the order is revoked under section 61A(6) or 61B(8); (b) if the order is revised in pursuance of paragraph 2 of Schedule 4A so that it ceases to grant planning permission in respect of the development or materially changes any condition or limitation to which the grant of permission is subject; (c) by the issue of a direction under powers conferred by the order. (4) The power under this section to include provision in a development order or a local development order may be exercised differently for different purposes.