(a) Pay off and cancellation of bonds.--In order to facilitate the extinguishment of the county debt, the county bonds purchased by the sinking fund commission shall be paid off and canceled according to the priority of maturity. The commission may, at the commission's discretion, withhold the purchase of the maturing county bonds until after bonds purchased from a later issue of county bonds shall be paid off and canceled.
(b) Sale of bonds.--If the sinking fund commission does not have sufficient money to meet the payment of the earlier maturing bonds, the bonds shall be sold by the commission at not less than par.