(a) Where an order to show cause is issued, any person having objections to the rates specified in such order shall file with the DOT decisionmaker an answer within forty-five (45) days after the date of service of such order or within such other period as the order may specify.

(b) An answer to an order to show cause shall contain specific objections, and shall set forth the findings and conclusions, the rates, and the supporting exhibits that would be substituted for the corresponding items in the findings and conclusions of the show cause order, if such objections were found valid.

(c) An answer filed by a person who is neither a party nor a person ultimately permitted to intervene in an oral evidentiary hearing if such proceeding is established shall be treated as a memorandum filed under § 302.706.