14.5.1 If there is a material change in the nature or basis of any Index, or if any Index is discontinued, the Parties shall seek to agree upon an alternative to that Index which as closely replicates the relevant Index as is possible, and such consequential changes shall be made to the calculations provided for in this paragraph 14 as are necessary to ensure that all payments to be made pursuant to this Contract shall be the same as if such change had not occurred. Any dispute regarding changes to the Index and/or calculations may be referred by either Party to the Disputes Resolution Procedure.
14.5.2 If any error or mistake shall occur in the publication for the figures for the relevant Index which have been used at any time in any calculation pursuant to this Schedule which is subsequently duly acknowledged and corrected by the Office of National Statistics or the relevant body with responsibility for the publication of such Index, the calculations in which the incorrect figures were used for the adjustments of any part of the Monthly Unitary Charge shall be recalculated using the correct figures. Any dispute regarding the recalculations pursuant to this paragraph 14 may be referred at the request by either Party to the Disputes Resolution Procedure. Any overpayment or underpayment by either Party to the other which has occurred as a result of the incorrect figures shall be paid or repaid by the Party to the other within [7] Business Days of the recalculation being agreed or determined (as the case may be).