Me. Rev. Stat. tit. 18-C, § 3-302

Upon receipt of an application requesting informal probate of a will, the register upon making the findings required by section 3-303 shall issue a written statement of informal probate if at least 120 hours have elapsed since the decedent's death. Informal probate is conclusive as to all persons until superseded by an order in a formal testacy proceeding. No defect in the application or procedure that leads to informal probate of a will renders the probate void.