(b)
An agency may pay expenses under subsection (a)(1) of this section only after the individual selected for appointment agrees in writing to remain in the Government service for a minimum period of—
(1)
one school year as determined under chapter
25 of title
20, if selected for appointment to a teaching position, except as a substitute, in the Department of Defense under that chapter; or
(2)
12 months after his appointment, if selected for appointment to any other position;
unless separated for reasons beyond his control which are acceptable to the agency concerned. If the individual violates the agreement, the money spent by the Government for the expenses is recoverable from the individual as a debt due the Government.