During the pendency of a formal testacy proceeding, the clerk shall not act upon any application for informal probate of any will of the decedent or any application for informal appointment of a personal representative of the decedent.
Formal Proceeding Supersedes All Informal Applications
Mont. Code Ann. § 72-3-303, under Formal Testacy and Appointment Proceedings.
Mont. Code Ann. § 72-3-303