4.—(1) Regulation 12 does not affect any proceedings where the date of knowledge has occurred before 1st October 2011.
(2) In those circumstances, regulation 47D of the Public Contracts Regulations shall have effect as if paragraph (2) provided—
“(2) Subject to paragraphs (3) and (4), such proceedings must be started within 3 months beginning with the date when the economic operator first knew or ought to have known that grounds for starting the proceedings had arisen.”.