Firstly, it is not a compensation event if the change to the Contractor's Works Information is being made either at the Contractor's request or to comply with other Works Information provided by the Employer (see clause 60.1 (1). Consequently, there would be a zero assessment in accordance with clause 61.4.
If the change to the Contractor's Works Information is because there is an ambiguity or inconsistency within it, then the event is assessed as if the Prices, the Completion Date and the Key Dates were for the interpretation most favourable to the Employer (see Clause 63.8). For example, if one part of their Works Information says the Contractor will provide gold plated taps, while the another says chrome, and it is resolved as gold, then it will be presumed that the Contractor has priced for gold plated taps and there will be no upward adjustment to the Prices. On the other hand, if the Project Manager is happy with chrome, then the Prices would be reduced to reflect the reduced specification.