4For the purposes of section 33 of this Act (preventive works for existing buildings, structures or works)—
(a)any unreasonable withholding of consent to the execution of preventive works under section 4(1)(a) of the 1957 Act shall have effect as an unreasonable withholding of consent to the execution of such works under paragraph (a) of subsection (2);
(b)any undertaking given by the Corporation under section 4(1)(b) of that Act shall have effect as an undertaking given under paragraph (b) of that subsection; and
(c)any requirement imposed by the Corporation under section 4(1)(b) of that Act, or any unreasonable failure to comply with any such requirement, shall have effect as a request made by the Corporation under that paragraph, or an unreasonable failure to comply with such a request.