10 U.S.C. § 1110a

(a) In General .— (1) As soon as practicable, the Secretary of Defense shall notify each individual described in subsection (b)— (A) that the individual is no longer eligible for health care benefits under the TRICARE program under this chapter; and (B) of options available for enrollment of the individual in the supplementary medical insurance program under part B of title XVIII of the Social Security Act ( 42 U.S.C. 1395j et seq.). (2) In carrying out this subsection, the Secretary of Defense shall— (A) establish procedures for identifying individuals described in subsection (b); and (B) consult with the Secretary of Health and Human Services to accurately identify and notify such individuals. (b) Individuals Described .— An individual described in this subsection is an individual who is— (1) a covered beneficiary; (2) entitled to benefits under part A of title XVIII of the Social Security Act ( 42 U.S.C. 1395c ) under section 226(b) or section 226A of such Act ( 42 U.S.C. 426(b) and 426–1); and (3) eligible to enroll in the supplementary medical insurance program under part B of such title ( 42 U.S.C. 1395j et seq.).