Sts. & Hy. Code, § 9453

If no proposals are received at a price of less than par and accrued interest, or if an insufficient amount of bonds are tendered at less than par and accrued interest to exhaust, as nearly as possible, the money available for purchase of bonds, the treasurer shall set aside a sum sufficient to pay the principal and accrued interest to the next interest payment date of the bonds to be called for redemption and shall proceed to call for redemption, in numerical order, at par and accrued interest to the next interest payment date, such outstanding bonds as can be retired from said funds.