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249. A revised decision given by a deciding officer in respect of a claim under section 23 of the Act of 1982, shall take effect as follows:—

(a) where an allowance is disallowed or reduced and the revised decision is given owing to the original decision having been given, or having continued in effect, by reason of any statement or representation (whether written or verbal) which was, to the knowledge of a person making it, false or misleading in a material respect or by reason of the wilful concealment of any material fact, it shall take effect as from the date on which the original decision took effect, but the original decision may, in the discretion of the deciding officer continue to apply to any period covered by the original decision to which such false or misleading statement or representation or such wilful concealment of any material fact does not relate ;

(b) where any allowance will, by virtue of the revised decision, be disallowed or reduced and the revised decision is given in the light of new evidence or new facts which have been brought to the notice of the deciding officer since the original decision was given, it shall take effect from such date as that officer shall determine having regard to the new facts or new evidence ;

(c) in any other case, it shall take effect as from the date considered appropriate by the deciding officer but any payment of an allowance already made at the date of the revision shall not be affected.

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