NEC 4 Option B - Late assessment of Compensation Event and Impact to Interim Payment

An Option B ECC contract is being used to construct a new road. Secondary Options X1. The Project Manager fails to make an assessment of the compensation event. An assessment is eventually made four months later. The Contractor had undertaken the work within one week of the original instruction and is complaining about the impact of this late assessment on its cash flow.

How should this be dealt with in the next payment certificate?

Before the next payment due, I think both parties to arrange to early warning to review if any impact for cashflow issue and the contractor is entitled to claim as per clasue 60.1(18). However, the Contractor’s quotaiton is not “deemed acceptance” as no second notice was issued to the PM as per clause 62.6.

As the payment is based on clause 50.2. That mean the Contractor suffer the cashflow issue from few months ago. So the Contractor is entitled if any additional cost (interest?)