The Works Information prepared by the Employer specified a lift with a required performance, but the Contractor could buy an alternative lift at much lover cost. He had included reference to this alternative in his revised Activity Schedule, which was accepted by PM. When the alternative lift arrives on site PM instructs Contractor to comply with the requirements of the contract.Is Contractor entitled to a Compensation Event as he will now incur significant additional cost and delay?
No this is not a compensation event. By accepting the design, they are assuming it fully complies with the original Works Information (see clause 14.1). If the Contractor knew they were proposing it as an alternative, they should have got that agreed by the Project Manager and received an instruction to change to the proposed before the design was issued. By changing it in a design (by stealth) does not mean if accepted that they have got away with it.
Some Contractors then ask what is the point of acceptance at all? It is not meaningless, it just doesn’t mean as much as the Contractor wants it to mean. It is the Contractor obligation to comply with the original requirements - it is not the project Manager to trawl through the submission and make sure they have, and take liability for anything they haven’t by accepting.