If the Contractor has not submitted a quotation for an additional activity within the time frame nor has requested an extension of time, what happens next?
Very simple. The Project Manager should (not may) assess the event them-self(clause 64.1) and advise the Contractor of their assessment which is then “implemented” under the contract.
Only formal recourse to the Contractor if they did not agree with the assessment would be adjudication.
It is important that the compensation event process is maintained so as to maintain the greater certainty of outcome for all involved. PMs need to ensure that they do step in as required by the contract.