; or (2) would cause serious harm to the national security of the United States. (c) Nature of relief (1) In general The relief the President is authorized to provide under this subsection is as follows: (A) (i) With respect to a determination relating to an investigation under section 322(a)(1), the denial or imposition of limitations on a request for a new grant of authority by the persons of Mexico that are the subject of the investigation. (ii) With respect to a determination relating to an investigation under section 322(a)(1), the revocation of, or restrictions on, grants of authority issued to the persons of Mexico that are the subject of the investigation since the date of the petition, request, or resolution. (B) With respect to a determination relating to an investigation under section 322(a)(2) or (3), the revocation or imposition of limitations on an existing grant of authority by the persons of Mexico that are the subject of the investigation. (C) With respect to a determination relating to an investigation under section 322(a)(1), (2), or (3), a cap on the number of grants of authority issued to persons of Mexico annually. (2) Deadline for relief Not later than 15 days after the date on which the President determines the relief to be provided under this subsection, the President shall direct the Secretary of Transportation to carry out the relief. (d) Period of relief (1) In general Subject to paragraph (2), any relief that the President provides under this section may not be in effect for more than 2 years. (2) Extension (A) In general Subject to subparagraph (C), the President, after receiving a determination from the Commission under subparagraph (B) that is affirmative, or which contains a determination that the President may treat as affirmative in accordance with section 330(d)(1) of the Tariff Act of 1930 ( 19 U.S.C. 1330(d)(1)(1) ), may extend the effective period of relief provided under this section by up to an additional 4 years, if the President determines that the provision of the