Scenario is - NEC3 ECC with Main Option A. Drawings state that a particular material is required for works, Specification states a different (cheaper) material. Contractor notifies an Early Warning and Project Manager confirms it is the more expensive material, as per drawings, that is to be used. No Compensation Event is issued as the PM states there is no change to the Works Information, just a clarification of which material is to be used. Contractor has bid on the cost of the cheaper material. Is this just Contractor risk at pricing? Or should the Specification have been updated to reflect the change in material, thus becoming a change to the WI and thus a 60.1(1).
That’s a change to the Works Information and a compensation event. You should notify in accordance with 17.1 (That’s an NEC3 clause number). The PM is obliged to instruct (not clarify) and will presumably change the reference to the cheaper material to the more expensive one.
That’s a CE under 60.1(1) because the WI has changed. Clause 63.8 tells you that in this kind of CE the baseline is the ‘interpretation most favourable to the Party which did not provide the Works Information’ - fairly clear in this case; the baseline is the cheaper material. Your CE is for the difference.