Any amendment, or purported amendment, of an access agreement shall be void unless the amendment has been approved by the Office of Rail and Road or is made pursuant to directions under section 22A or 22C below or Schedule 4A to this Act.
The Office of Rail and Road may, for the purposes of subsection (1) above, give the parties to any particular access agreement its general approval to the making to that access agreement of amendments of a description specified in the approval; and any approval so given shall not be revoked.
The Office of Rail and Road may, for the purposes of subsection (1) above, give its general approval to the making to access agreements, or to access agreements of a particular class or description, of amendments of a description specified in the approval.
Where the Office of Rail and Road gives or revokes a general approval under subsection (3) above, it shall publish the approval or revocation (as the case may be) in such manner as it considers appropriate.
The revocation of a general approval given under subsection (3) above shall not affect the continuing validity of any amendment made in accordance with, and before the revocation of, that approval.
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Neither the CMA nor the Office of Rail and Road may exercise, in respect of an access agreement, the powers given by section 32 (enforcement directions) or section 35(2) (interim directions) of the Competition Act 1998.
Subsection (6A) does not apply to the exercise of the powers given by section 35(2) in respect of conduct—