the satisfaction of the Commissioner of Social Security that the individual intends to continue to be in full-time attendance at a secondary school or institution described in section 102 of the Higher Education Act of 1965 ( 20 U.S.C. 1002 ) immediately following such period. An individual who does not meet the requirement of clause (ii) with respect to such period of nonattendance shall be deemed to have met such requirement (as of the beginning of such period) if he is in full-time attendance at such a school or institution immediately following such period. (G) A child who attains age 22 at a time when the child is a full-time student of an educational institution (as defined in subparagraph (E) and without application of subparagraph (F)) but has not (at such time) completed the requirements for, or received, a diploma or equivalent certificate from a secondary school (as defined in subparagraph (C)(i)) or, if such child is a student at an educational institution described in section 102 of the Higher Education Act of 1965, a diploma, degree, or equivalent degree from such an institution, shall be deemed (for purposes of determining whether the child's entitlement to benefits under this subsection has terminated under paragraph (1)(F) and for purposes of determining his initial entitlement to such benefits under clause (iii) of paragraph (1)(B)) not to have attained such age until the first day of the first month following the end of the quarter or semester in which he is enrolled at such time (or, if the secondary school or educational institution in which he is enrolled is not operated on a quarter or semester system, until the first day of the first month following the completion of the course in which the child is so enrolled or until the first day of the third month beginning after such time, whichever first occurs). . (2) Effective date The amendments made by this subsection shall apply to child's insurance benefits that are payable for months beginning on or after January 1, 2024. (b) Railroad