A motion for consolidation of two or more Proceedings shall be in writing, signed by the movant or his Authorized Representative, and filed with the Executive Director or Examiner at least ten (10) days prior to the date set for hearing. No two or more Proceedings shall be consolidated or heard jointly without the consent of all Parties to all such Proceedings, unless the Board, its designee, the Executive Director or Examiner find that the two or more Proceedings involve some or all of the same Parties, common questions of law or fact, or both, and shall further find that separate hearings would result in unwarranted expense, delay, or substantial injustice. Separate hearings on distinct issues may also be allowed where such hearings are in the interest of justice, or upon the agreement of all Parties to the Proceeding pursuant to §67.11 of this chapter (relating to agreements to be in writing).