19.5.10.1 . If the Authority and Contractor disagree over whether an incident of unavailability has arisen or whether it has been rectified then the Authority's decision shall prevail for the purposes of calculating unavailability deductions. If this is not reflected in the calculation of the monthly unitary charge the Authority shall be entitled to withhold payment of the relevant deduction. The Contractor may refer the matter to the dispute resolution procedure. (See Section 34 (Dispute Resolution)).
Required drafting is as follows:
19.5.10.1 If either party disputes the other's entitlement to any payment claimed by the other pursuant to or arising out of this Contract the provisions of this Clause 28 shall apply. Any Disputed Amount may be withheld pending agreement or determination of the rights and obligations of the parties in relation to the Disputed Amount but any undisputed amounts shall be paid when due.