18.1 Sub-hubco and the Authority shall, within [ ] Business Days following the Actual Completion Date [Phase Actual Completion Date], respectively undertake and complete Sub-hubco's Post-Completion Commissioning and the Authority's Post Completion Commissioning, in accordance with the Final Commissioning Programme [for the relevant Phase]. Both parties shall, at all times, and in particular in the period between the Actual Completion Date [Phase Actual Completion Date] and the Actual Commissioning End Date [for the relevant Phase], use reasonable endeavours to assist the other party to ensure compliance with the Final Commissioning Programme [for the relevant Phase].