(3) A conditional adjustment of the rent charged shall be subject to subsequent modification by the final decision of the Rent Administrator on the petition. If a hearing has been held on the petition, the Rent Administrator shall, by order served upon the parties at least 10 days before the expiration of the 90-day period commenced pursuant to paragraph (2) of this subsection, make a provisional finding as to the rent increase justified by the order, if any. Except to the extent modified pursuant to § 42-3502.06 or this section, the adjustment procedures of § 42-3502.16 shall apply to any adjustment.
(4) If the Rent Administrator denies the requested rent increase or approves a rent increase that is less than the amount of the conditional adjustment of the rent charged by the housing provider, the housing provider shall refund to the tenant within 21 days of the Rent Administrator's order any rent paid in excess of the amount approved by the Rent Administrator, except that the tenant may elect within 14 days of the Rent Administrator's order to apply any amount of the refund not yet refunded by the housing provider to the tenant, as a credit against future rental payments.