(a) The commission may use any portion of the surplus under Section 204.065 that is not used to pay bond obligations to compute a surplus credit for an employer entitled to an experience rate on the computation date, to be applied beginning with contributions for the first quarter of the following year.
(b) The amount of the surplus credit is computed by multiplying the surplus ratio computed under Section 204.066 by the employer’s contributions due for the four calendar quarters ending the preceding September 30.

(c) An employer may not apply a surplus credit against delinquent contributions. A surplus credit may not be applied until the employer has paid any delinquent contributions.