; and (2) by striking within ninety days after the effective date of this amendatory Act and inserting within 90 days after the effective date of this amendatory Act, or, in the case of any person engaged in the transportation of natural gas described in section 2(5)(C), within 90 days after the date of enactment of the Building American Energy Security Act of 2023 . (c) Savings clause Nothing in this section or an amendment made by this section authorizes the Federal Energy Regulatory Commission— (1) to order a natural-gas company under section 7(a) of the Natural Gas Act ( 15 U.S.C. 717f(a) ) to extend or modify the transportation facilities of the natural-gas company used for natural gas described in subparagraph (A) or (B) of section 2(5) of that Act ( 15 U.S.C. 717a(5) ) to transport natural gas described in subparagraph (C) of that section; or (2) to attach to a certificate of public convenience and necessity issued under section 7(e) of the Natural Gas Act ( 15 U.S.C. 717f(e) ) any requirement that transportation facilities used for natural gas described in subparagraph (A) or (B) of section 2(5) of that Act ( 15 U.S.C. 717a(5) ) be capable of transporting natural gas described in subparagraph (C) of that section. 203. Authorization of Mountain Valley Pipeline (a) Finding Congress finds that the timely completion of the construction of the Mountain Valley Pipeline— (1) is necessary— (A) to ensure an adequate and reliable supply of natural gas to consumers at reasonable prices; (B) to facilitate an orderly transition of the energy industry to cleaner fuels; and (C) to reduce carbon emissions