The deputy shall promptly notify the claimant and any other interested party of the determinations and reasons therefor for the determinations. Subject to subsection 11, unless the claimant or any such interested party, within 15 calendar days after that notification was mailed to his the claimant's last known address, files an appeal from that determination, that determination shall be is final, provided except that the period within which an appeal may be filed may be extended, for a period not to exceed an additional 15 calendar days, for good cause shown. If new evidence or pertinent facts that would alter that determination become known to the deputy prior to the date that determination becomes final, a redetermination is authorized, but that redetermination must be mailed before the original determination becomes final.

If an employer's separation report for an employee is not received by the office specified thereon on the separation report within 10 days after that report was requested, the claim shall must be adjudicated on the basis of information at hand. If the employer's separation report containing possible disqualifying information is received after the 10-day period and the claimant is denied benefits by a revised deputy's decision, benefits paid prior to the date of the revised decision shall do not constitute an overpayment of benefits. Any benefits paid after the date of the revised decision shall constitute an overpayment.

If an employer files an amended separation report or otherwise raises a new issue as to the employee's eligibility or changes the wages or weeks used in determining benefits which that results in a denial of benefits or a reduction of the weekly benefit amount, the benefits paid prior to the date the determination is mailed shall do not constitute an overpayment. Any benefits received after that date to which the claimant is not entitled pursuant to a new determination based on that new employer information shall constitute an overpayment.

If, during the period a claimant is receiving benefits, new information or a new issue arises concerning the claimant's eligibility for benefits or which affects the claimant's weekly benefit amount, no benefits may not be withheld until a determination is made on the issue. Before a determination is made, written notice shall be mailed to the claimant and other interested parties, which shall must include the issue to be decided, the law upon which it is based, any factual allegations known to the bureau, the right to a fact-finding interview, the date and location of the scheduled interview and the conduct of the interview and appeal. The fact-finding interview shall must