The Commission shall use its best endeavours to secure that its work is completed as soon as practicable and in any event by the end of the transitional period.

In this paragraph “the transitional period” means the period of three years beginning with the commencement of section 40.

Subject to sub-paragraph (4), the Commission shall be wound up at the end of the transitional period.

The Secretary of State may by order provide for sub-paragraph (3) to have effect with the substitution for the transitional period of such longer period as may be specified in the order.