Nothing in this section shall exempt from the jurisdiction of the Commission under the Natural Gas Act [
15 U.S.C. 717 et seq.] any transportation in interstate commerce of natural gas, any sale in interstate commerce for resale of natural gas, or any person engaged in such transportation or such sale to the extent such transportation, sale, or person is subject to the jurisdiction of the Commission under such Act without regard to the transfer of contractual interests pursuant to the rule required under subsection (a)(1).