Where pursuant to any provision of this Part 22 of the Schedule the Board is to pay a capital sum in respect of a Qualifying Variation:
(a) the Board and Project Co shall agree:
(i) a payment schedule in respect of the payment of such sum reflecting the amount and timing of the costs to be incurred by Project Co in carrying out the Qualifying Variation to the extent borne by the Board; and
(ii) where payment for part of the Qualifying Variation reflects the carrying out of, or specific progress towards, an element within the Qualifying Variation, an objective means of providing evidence confirming that the part of the Qualifying Variation corresponding to each occasion when payment is due under the payment schedule appears to have been duly carried out,
(such payment schedule and evidence to be determined in accordance with Part 26 of the Schedule (Dispute Resolution Procedure) in the event of the Board and Project Co failing to agree as to its terms) provided that where all or any part of the Qualifying Variation is being carried out by a third party under a contract with Project Co, subject to the terms of any contract between Project Co and that third party in relation to the implementation of the Qualifying Variation having been approved by the Board (such approval not to be unreasonably withheld), the process under Part 26 of the Schedule (Dispute Resolution Procedure) shall not determine a payment schedule or evidence which would not enable Project Co to be funded by the Board in time to make payments to that third party in accordance with its contract with Project Co;
(b) the Board shall make payment to Project Co within fifteen (15) Business Days of receipt by the Board of invoices presented to the Board (in all material respects) in accordance with the agreed payment schedule (as the case may be, varied by agreement from time to time) accompanied by the relevant evidence (where applicable) that the relevant part of the Qualifying Variation has been carried out; and
(c) if payment is not made in accordance with sub-paragraph (b) above, the Board shall pay interest to Project Co on the amount unpaid from the date fifteen (15) Business Days after receipt of the relevant invoice until paid at the Default Interest Rate.