Administrative action under the provisions of or amendments made by this subtitle or part 2 of the Conrail Privatization Act [
45 U.S.C.
1311 et seq.] which is subject to review shall be upheld unless such action is found to be unlawful under standards established for review of informal agency action under paragraphs (2)(A), (B), (C), and (D) of section
706 of title
5. The requirements of this subtitle or part 2 of the Conrail Privatization Act [
45 U.S.C.
1311 et seq.], as the case may be, shall constitute the exclusive procedures required by law for such administrative action.