At least 14 days before the date of the hearing, or no later than the next business day after the issuance of the certification if the date between certification and hearing is less than 14 days, each party shall submit to the members of the panel and to the other party written proposals on all of the issues it intends to submit to arbitration. Parties are not entitled to submit issues that were not among the issues certified under WAC 391-55-200.