308. Supervening illegality.

Where, during the course of the works, it becomes illegal to perform the contract at all, the contract will be frustrated and both parties will be discharged1. However, the contract will not necessarily be frustrated where the illegality affects only one of the contractor's obligations or the time at which the contract is to be performed2. If the execution of the works is rendered illegal for a period of time longer than any delay contemplated by the parties at the time of the contract, the contract will be frustrated