Section 39.20.150 - Advances and recovery(a) An agency may advance, through proper disbursing methods, to a person entitled to per diem or mileage allowance under AS 39.20.110 - 39.20.170 the sums considered advisable considering the character and probable duration of the travel to be performed.(b) Sums advanced and not used for allowable travel expense are recoverable by setoff against salary due, or otherwise, from the person to whom advanced, or the person's estate, by deduction from any amount due from the state, or by other legal methods of recovery that may be necessary.