; or (ii) enrolls under this part on or after the date of the enactment of this Act and before the end of the special enrollment period under paragraph (1)(A), for premiums for months during the coverage period under this part which occur during or after the effective month. (C) Loss of reduction if individual terminates enrollment Subparagraph (A) shall not apply to a transition individual if the individual terminates enrollment under this part after the end of the special enrollment period under paragraph (1). (3) Transition individual defined In this section, the term transition individual means an individual who resides in Puerto Rico and who would have been deemed enrolled under this part pursuant to section 1837(f) before the first day of the effective month but for the fact that the individual was a resident of Puerto Rico, regardless of whether the individual is enrolled under this part as of such first day. . III Medicare Advantage (Part C) 231. Adjustment in benchmark for low-base payment counties in Puerto Rico Section 1853(n) of the Social Security Act ( 42 U.S.C. 1395w–103(n) ) is amended— (1) in paragraph (1), by striking and (5) and inserting , (5), and (6) ; (2) in paragraph (4), by striking In no case and inserting Subject to paragraph (6), in no case