This section applies if the Secretary of State or an inspector issues a decision document which contains a correctable error.
The Secretary of State or the inspector (as the case may be) may correct the error—
if he is requested to do so in writing by any person;
if he sends a statement in writing to the applicant which explains the error and states that he is considering making the correction.
But the Secretary of State or inspector must not correct the error unless—
not later than the end of the relevant period he receives a request mentioned in subsection (2)(a) or sends a statement mentioned in subsection (2)(b), and
he informs the local planning authority of that fact, ...
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The relevant period—
is the period within which an application or appeal may be made to the High Court in respect of the decision recorded in the decision document;
does not include any time by which such a period may be extended by the High Court.
It is immaterial whether any such application or appeal is made.
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