(a) A personal representative or any interested person may petition for an order of complete settlement of the estate. The personal representative may petition at any time, and any other interested person may petition after one year from the appointment of the original personal representative except that no petition under this section may be entertained until the time for presenting claims which arose prior to the death of the decedent has expired. The petition may request the court to determine testacy, if not previously determined, to consider the final account or compel or approve an accounting and distribution, to construe any will or determine heirs and adjudicate the final settlement and distribution of the estate. After notice to all interested persons and hearing, the court may enter an order or orders, on appropriate conditions, determining the persons entitled to distribution of the estate and, as circumstances require, approving settlement and directing or approving distribution of the estate and discharging the personal representative from further claim or demand of any interested person.

(b) If one or more heirs or devisees were omitted as parties in, or were not given notice of, a previous formal testacy proceeding, the court, on proper petition for an order of complete settlement of the estate under this section, and after notice to the omitted or unnotified persons and other interested parties determined to be interested on the assumption that the previous order concerning testacy is conclusive as to those given notice of the earlier proceeding, may determine testacy as it affects the omitted persons and confirm or alter the previous order of testacy as it affects all interested persons as appropriate in the light of the new proofs. In the absence of objection by an omitted or unnotified person, evidence received in the original testacy proceeding shall constitute prima facie proof of due execution of any will previously admitted to probate, or of the fact that the decedent left no valid will if the prior proceedings determined this fact.