2.1 An Authority Change Notice for a Medium Value Change must:
2.1.1 state that it refers to a Medium Value Change;
2.1.2 set out the change in the Works or Services or the additional works or services required in sufficient detail to enable Sub-hubco to calculate and provide the Estimated Change in Project Costs in accordance with paragraph 3 (Contractor's Estimate) of this Section 3 (Medium Value Changes);
2.1.3 set out whether, in respect of any additional facilities, Sub-hubco is expected to provide [facilities management services and lifecycle maintenance services] in respect of such additional facilities; and
2.1.4 set out the timing of the additional works or services required by the Authority.
2.2 Within fifteen (15) Business Days of receipt of the Medium Value Change Notice, Sub-hubco must notify the Authority in writing:
2.2.1 whether it considers that it is entitled to refuse the Medium Value Change on any of the grounds set out in paragraphs 1.2.1 to 1.2.6 of this Section 3;
2.2.2 when it will provide the Estimate to the Authority bearing in mind the requirement in paragraph 7.2.2 of this Section 3; and
2.2.3 its estimate of the Third Party Costs that it will incur to prepare the Estimate.
2.3 If Sub-hubco notifies the Authority that it considers that it is entitled to refuse the Medium Value Change on one or more of the grounds set out in paragraphs 1.2.1 to 1.2.6 of this Section 3, then unless the parties otherwise agree, the Authority shall be deemed to have withdrawn the Authority Notice of Change if it has not referred the matter to the Dispute Resolution Procedure within [twenty (20)] Business Days of receipt of Sub-hubco's notice.
2.4 If the Authority considers that Sub-hubco's proposed time for providing the Estimate is not reasonable, the parties shall endeavour to agree the time, failing which the matter may be referred to the Dispute Resolution Procedure.
2.5 If the Authority considers that the Sub-hubco's estimate of Third Party Costs to prepare the Estimate is not reasonable, the parties shall endeavour to agree the same, failing which the matter may be referred to the Dispute Resolution Procedure.
2.6 If any matter is referred to the Dispute Resolution Procedure pursuant to paragraph 2 (Medium Value Change Notice) of this Section 3 (Medium Value Changes), the time for Sub-hubco to provide the Estimate shall be counted from the date of determination of that dispute if the dispute is determined in Sub-hubco's favour.