26.—(1) Where there is a subsequent decision, the effective date of which is the case conversion date, the amount of child support maintenance payable shall be calculated as if the subsequent decision were a conversion decision.
(2) For the purposes of paragraph (1), regulations 9 to 25 shall apply as if references—
(a)to the calculation date, including in relation to the definition of the former assessment amount, were to—
(i)where there has been a decision under Article 18, 19 or 22 of the Order in relation to the maintenance assessment, the effective date of that decision, or
(ii)where head (i) does not apply—
(aa)the effective date of the subsequent decision; or
(bb)if earlier, the date the subsequent decision was made;
(b)to the new amount were to the subsequent decision amount; and
(c)to the conversion decision in regulation 24(3) were to the subsequent decision.