11. It shall be the duty of each supplier to—

(a) account to the Commission, the transmission system operator or distribution system operator, as appropriate, for all transactions relating to the PSO Levy or PSO Payment,

(b) pay any additional benefits due under Article 8(1) to the transmission system operator,

(c) invoice final customers for the PSO Levy or credit final customers for the PSO Payment on the basis notified to them by the Commission,

(d) collect from final customers the amount of the PSO Levy or credit to final customers the amount of the PSO Payment payable in respect of each such final customer account in accordance with the provisions of Schedule 2, and

(e) pay to the transmission system operator or distribution system operator, as appropriate, all amounts invoiced by such supplier in respect of the PSO Levy.]