Sec. 3. Every personal representative may file in the court a verified account of his administration at any time prior to final settlement and distribution but every personal representative must file in the court a verified account of his administration.
(a) Upon filing a petition for final settlement;
(b) Upon the revocation of his letters;
(c) Upon his application to resign and before his resignation is accepted by the court;
(d) At any other time when directed by the court either of its own motion or on the application of any interested person.