This section applies where—
If the local planning authority are of the opinion that the development will not be completed within a reasonable period, they may serve a notice ("a completion notice") stating that the planning permission will cease to have effect at the expiration of a further period specified in the notice.
The period so specified must not be less than 12 months after the notice takes effect.
A completion notice shall be served—
The local planning authority may withdraw a completion notice at any time before the expiration of the period specified in it as the period at the expiration of which the planning permission is to cease to have effect.
If they do so they shall immediately give notice of the withdrawal to every person who was served with the completion notice.