(a) A veteran eligible for reemployment under this chapter must apply for reemployment not later than the 90th day after the date the veteran is discharged or released from active military service.
(b) An application for reemployment must:
(1) be made to the head of the department, office, commission, or board of this state, the state institution, or the local governmental entity that employed the veteran before the veteran entered military service;
(2) be in writing; and
(3) have attached to it evidence of the veteran's discharge, separation, or release from military service under honorable conditions.