20.—(1) Where the rights and liabilities under a relevant arrangement are vested in a participant authority, or a participant authority and any other local authority or the Residuary Body jointly and severally, the participant authority’s credit ceiling shall be adjusted on the vesting day by—
(a)adding to it an amount equal to the determined amount for the arrangement in question; and
(b)deducting from it an amount equal to the aggregate of T and U as determined for the arrangement in question.
(2) Where the rights and liabilities under an excluded arrangement are vested in a participant authority, or a participant authority and any other local authority or the Residuary Body jointly and severally, the participant authority’s credit ceiling shall be adjusted on the vesting day by deducting from it an amount equal to the aggregate of R, T and U as determined for the arrangement in question.