; and (ii) a detailed explanation of any significant modifications in requirements or resources, as compared to the plan submitted under that paragraph. (b) Form The plans required under subsection (a) shall be submitted in unclassified form, but may include a classified annex. 1242. Modification of reporting requirements relating to the Open Skies Treaty (a) Plan for implementation flights Section 1235(a) of the National Defense Authorization Act for Fiscal Year 2018 ( Public Law 115–91 ; 131 Stat. 1660) is amended— (1) in paragraph (1)— (A) by striking the President and inserting the Secretary of Defense ; and (B) by striking with respect to such fiscal year and inserting with respect to the calendar year in which the flight is to be conducted ; (2) in paragraph (2), by striking during such fiscal year and inserting during such calendar year ; and (3) in paragraph (3), by striking with respect to a fiscal year and inserting with respect to a calendar year . (b) Quarterly reports on observation flights by the Russian Federation (1) In general Paragraph (1) of subsection (c) of section 1236 of the National Defense Authorization Act for Fiscal Year 2017 ( Public Law 114–328