A program of educational assistance established under this chapter shall provide that any person enlisting or reenlisting in an armed force under the jurisdiction of the Secretary of the military department concerned who meets the eligibility requirements established by the Secretary in accordance with subsection (b) shall, subject to paragraph (3), become entitled to educational assistance under section 2143 of this title at the time of such enlistment.

The period of educational assistance to which such a person becomes entitled is one standard academic year (or the equivalent) for each year of the enlistment of such person, up to a maximum of four years. However, if the person is discharged or otherwise released from active duty after completing two years of the term of such enlistment but before completing the full term of such enlistment (or before completing four years of such term, in the case of an enlistment of more than four years), then the period of educational assistance to which the person is entitled is one standard academic year (or the equivalent) for each year of active service of such person during such term. For the purposes of the preceding sentence,

a portion of a year of active service shall be rounded to the nearest month and shall be prorated to a standard academic year.

enlist or reenlist for service on active duty as a member of the Army, Navy, Air Force, or Marine Corps after September 30, 1980, and before October 1, 1981;

are graduates from a secondary school; and

meet such other requirements as the Secretary may consider appropriate for the purposes of this chapter and the needs of the armed forces.