“In the case of any individual—“(A) who performed active service (i) as a commissioned officer of the Public Health Service at any time during the period beginning July 4, 1952, and ending December 31, 1956, or (ii) as a commissioned officer of the Coast and Geodetic Survey at any time during the period beginning July 29, 1945, and ending December 31, 1956; and
“(B)(i) who became entitled to old-age insurance benefits under section 202(a) of the Social Security Act [42 U.S.C. 402(a)] prior to January 1, 1957, or
“(ii) who died prior to January 1, 1957, and whose widow, child, or parent is entitled for the month of January 1957, on the basis of his wages and self-employment income, to a monthly survivor’s benefit under section 202 of such act [42 U.S.C. 402]; and
“(C) any part of whose service described in subparagraph (A) was not included in the computation of his primary insurance amount under section 215 of such act [42 U.S.C. 415] but would have been included in such computation if the amendment made by paragraph (1) of this subsection or paragraph (1) of subsection (d) had been effective prior to the date of such computation,
the Secretary of Health, Education, and Welfare [now Health and Human Services] shall, notwithstanding the provisions of section 215(f)(1) of the Social Security Act [42 U.S.C. 415(f)(1)], recompute the primary insurance amount of such individual upon the filing of an application, after December 1956, by him or (if he dies without filing such an application) by any person entitled to monthly survivor’s benefits under section 202 of such act [42 U.S.C. 402] on the basis of his wages and self-employment income. Such recomputation shall be made only in the manner, provided in title II of the Social Security Act [42 U.S.C. 401 et seq.] as in effect at the time of the last previous computation or recomputation of such individual’s primary insurance amount, and as though application therefor was filed in the month in which application for such last previous computation or recomputation was filed. No recomputation made under this paragraph shall be regarded as a recomputation under section 215(f) of the Social Security Act [42 U.S.C. 415(f)]. Any such recomputation shall be effective for and after the twelfth month before the month in which the application was filed, but in no case for any month before January 1957.”