(1)If it appears to the local planning authority, having regard to the development plan and to any other material considerations, that it is expedient to revoke or modify any permission to develop land granted on an application made under this Part of this Act, the authority, subject to the following provisions of this section, may by order revoke or modify the permission to such extent as (having regard to those matters) they consider expedient.
(2)An order under this section shall not take effect unless it is confirmed by the Minister; and the Minister may confirm any such order submitted to him either without modification or subject to such modifications as he considers expedient.
(3)Where a local planning authority submit an order to the Minister for his confirmation under this section, the authority shall serve notice on the owner and on the occupier of the land affected and on any other person who in their opinion will be affected by the order; and if within such period as may be specified in that behalf in the notice (not being less than twenty-eight days from the service thereof) any person on whom the notice is served so requires, the Minister, before confirming the order, shall afford to that person, and to the local planning authority, an opportunity of appearing before, and being heard by, a person appointed by the Minister for the purpose.
(4)The power conferred by this section to revoke or modify permission to develop land may be exercised—
(a)where the permission relates to the carrying out of building or other operations, at any time before those operations have been completed ;
(b)where the permission relates to a change of the use of any land, at any time before the change has taken place:
Provided that the revocation or modification of permission for the carrying out of building or other operations shall not affect so much of those operations as has been previously carried out.