When an order and notice of assessment has been served upon or mailed to a delinquent employer, as heretofore provided, such employer may within thirty days thereafter file a petition in writing with the appeal tribunal, stating that such assessment is unjust or incorrect and requesting a hearing thereon. Such petition shall set forth the reasons why the assessment is objected to and the amount of contributions, if any, which said employer admits to be due the employment security department. If no such petition be filed with the appeal tribunal within thirty days, the assessment shall be conclusively deemed to be just and correct: PROVIDED, That in such cases, and in cases where payment of contributions, interest, or penalties has been made pursuant to a jeopardy assessment, the commissioner may properly entertain a subsequent application for refund. The filing of a petition on a disputed assessment with the appeal tribunal shall stay the distraint and sale proceeding provided for in this title until a final decision thereon shall have been made, but the filing of such petition shall not affect the right of the commissioner to perfect a lien, as provided by this title, upon the property of the employer. The filing of a petition on a disputed assessment shall stay the accrual of interest and penalties on the disputed contributions until a final decision shall have been made thereon.
Within thirty days after notice of denial of refund or adjustment has been mailed or delivered (whichever is the earlier) to an employer, the employer may file a petition in writing with the appeal tribunal for a hearing thereon: PROVIDED, That this right shall not apply in those cases in which assessments have been appealed from and have become final. The petitioner shall set forth the reasons why such hearing should be granted and the amount which the petitioner believes should be adjusted or refunded. If no such petition be filed within said thirty days, the determination of the commissioner as stated in said notice shall be final.