enrollment periods and effective date of coverage (a) Effective dates Section 1838(a) of the Social Security Act ( 42 U.S.C. 1395q(a) ) is amended— (1) by amending paragraph (2) to read as follows: (2) (A) in the case of an individual who enrolls pursuant to subsection (d) of section 1837 before the month in which he first satisfies paragraph (1) or (2) of section 1836, the first day of such month, (B) in the case of an individual not described in subparagraph (A) who first satisfies such paragraph in a month beginning before January 2019 and who enrolls— (i) pursuant to such subsection (d) in such month in which he first satisfies such paragraph, the first day of the month following the month in which he so enrolls, (ii) pursuant to such subsection (d) in the month following such month in which he first satisfies such paragraph, the first day of the second month following the month in which he so enrolls, or (iii) pursuant to such subsection (d) more than one month following such month in which he satisfies such paragraph, the first day of the third month following the month in which he so enrolls, (C) in the case of an individual not described in subparagraph (A) who enrolls pursuant to subsection (e) of section 1837 in a month beginning before January 2019, the July 1 following the month in which he so enrolls, (D) in the case of an individual not described in subparagraph (A) who first satisfies such paragraph in a month beginning on or after January 1, 2019, and who enrolls pursuant to such subsection (d) in such month in which he first satisfies such paragraph or in any subsequent month, the first day of the month following the month in which he so enrolls, or (E) in the case of an individual not described in subparagraph (A) who enrolls pursuant to subsection (e) of section 1837 in a month beginning on or after October 15, 2018, the first day of the month following the month in which he so enrolls.