An individual who transfers from service making the individual eligible for repayment of loans under this section (as described in subsection (a)(3)) to service making the individual eligible for repayment of loans under
section 16301 of title 10 (as described in subsection (a)(2) or (g) of that section) during a year shall be eligible to have repaid a portion of such loan determined by giving appropriate fractional credit for each portion of the year so served, in accordance with regulations of the Secretary concerned.