Subparagraphs (A) and (B) do not apply with respect to foreign national employees. Such provisions of the Foreign Service Act of 1980 [22 U.S.C. 3901 et seq.] (other than the provisions of section 309 [22 U.S.C. 3949]) as the President deems appropriate shall apply to individuals appointed or assigned under this paragraph, including in all cases, the provisions of section 310 of that Act [22 U.S.C. 3950], except that (i) the President may by regulation make exceptions to the application of section 310 [22 U.S.C. 3950] in cases in which the period of the appointment or assignment exceeds thirty months, (ii) members of the Foreign Service appointed or assigned pursuant to this paragraph shall receive within-class salary increases in accordance with such regulations as the President may prescribe, and (iii) under such regulations as the President may prescribe, individuals who are to perform duties of a more routine nature than are generally performed by members of the Foreign Service assigned to class 9 in the Foreign Service Schedule may be appointed to an unenumerated class ranking below class 9 in the Foreign Service Schedule and be paid basic compensation at rates lower than those for class 9, except that such rates may be no less than the then applicable minimum wage rate specified in section 206(a)(1) of title 29.

if such individual (i) served satisfactorily under the authority of this subsection, as certified by the President, for not less than thirty-six months on a continuous basis without a break in service of more than three days, and (ii) is qualified for the position in question.

At no time may the number of appointments or assignments of United States citizens in effect under paragraph (2) for periods in excess of five years exceed fifteen percent of the total of all appointments and assignments of United States citizens then in effect under paragraph (2).