Unemp. Ins. Code, § 1221

(a) Within 10 working days of notice of an assessment pursuant to Section 1137, the employer may file a petition for reassessment of the jeopardy assessment pursuant to Section 1222.

(b) Within five days of receiving a petition for reassessment pursuant to subdivision (a), the board shall notify the employer of the date and time of a preliminary hearing to determine the reasonableness of levying the assessment pursuant to Section 1137. The preliminary hearing shall be held before an administrative law judge and scheduled not less than 10 nor more than 20 days from the filing of the petition for reassessment. The administrative law judge shall issue a decision within 10 days of the scheduled hearing date. The date scheduled for the preliminary hearing may be continued by the administrative law judge upon the request of the employer and the director.

(c) The burden of proof on the issue of the reasonableness of levying the assessment pursuant to Section 1137 shall be on the director. In determining the reasonableness of levying the assessment pursuant to Section 1137 at the preliminary hearing, the administrative law judge shall consider and make findings on whether the director had probable cause under Section 1137.1 to levy the assessment pursuant to Section 1137. If the administrative law judge or the board, on appeal from an administrative law judge’s decision, decides that the assessment should not have been levied under Section 1137, the assessment shall automatically become, and shall have the effect of, an assessment pursuant to Section 1126 or 1127, whichever is applicable. If the administrative law judge or the board decides that the assessment was properly levied under Section 1137, this decision shall be incorporated in any decision rendered following the hearing pursuant to subdivision (d). The board shall expedite any appeal from an administrative law judge’s decision on a preliminary hearing.

(d) All other issues raised by a petition for reassessment filed pursuant to subdivision (a), including, but not limited to, the appropriateness of the amount assessed, shall be determined at a hearing scheduled and held pursuant to Sections 1223 and 1224.