(1) If the Secretary is satisfied that the rate at which a social security payment is being, or has been, paid is more than the rate provided for by the social security law, the Secretary is to:
(a) determine that the rate is to be reduced to the rate provided for by the social security law; and
(b) specify the last - mentioned rate in the determination.
(2) Subsection (1) does not authorise the Secretary to make a determination if:
(a) the rate at which a social security payment is payable to a person is reduced by the operation of another provision of the social security law; and
(b) the determination would take effect at or after the time at which the reduction referred to in paragraph (a) would take effect.