Mont. Code Ann. § 72-3-1011

Unless previously barred by adjudication and except as provided in the closing statement, the rights of successors and of creditors whose claims have not otherwise been barred against the personal representative for breach of fiduciary duty are barred unless a proceeding to assert the same is commenced within 6 months after the filing of the closing statement. The rights thus barred do not include rights to recover from a personal representative for fraud, misrepresentation, or inadequate disclosure related to the settlement of the decedent's estate.