The rules set forth in this subpart are applicable to proceedings forwarded pursuant to § 12.26(c) of the Reparation Rules. The rules in subpart B permitting discovery are applicable in a formal decisional proceeding, as supplemented by § 12.301. Unless specifically made applicable, the rules prescribed in subparts C and D shall not apply to formal decisional proceedings. Parties to a proceeding forwarded pursuant to § 12.26(c) may, by written agreement filed at any time prior to the issuance of an initial decision, or of any other order disposing of all issues in the proceeding, elect to have all issues in the proceeding decided pursuant to the voluntary decisional procedure. Upon receiving a timely filed stipulation signed by all parties evidencing such an election, the Administrative Law Judge shall conduct the proceeding and render a decision pursuant to subpart C of these rules.