The Commission shall, within the period of two years beginning with the date of the reference, prepare its report under section 142 and publish it under subsection (1) of section 143 or (as the case may be) give it to the Secretary of State under subsection (3) of that section.

The Secretary of State may by order amend subsection (1) so as to alter the period of two years mentioned in that subsection or any period for the time being mentioned in that subsection in substitution for that period.

No alteration shall be made by virtue of subsection (2) which results in the period for the time being mentioned in subsection (1) exceeding two years.

An order under subsection (2) shall not affect any period of time within which, in relation to a market investigation reference, the Commission is under a duty to prepare its report under section 142 and take action in relation to it under section 143(1) or (3) if the Commission is already under that duty in relation to that reference when the order is made.

Before making an order under subsection (2) the Secretary of State shall consult the Commission and such other persons as he considers appropriate.