Any fiduciary engaged in war service may be removed from his office as such upon petition filed in the proper court having jurisdiction by any person interested in the trust fund or the estate being administered or by any co-fiduciary or surety, and if the trust has not been fully executed or the administration of the estate has not been fully completed, the court, upon such removal, must appoint a successor fiduciary to fill the vacancy caused by such removal if there is no trust instrument providing a practicable method of appointment. If the court shall find that, because of the military service of the fiduciary, the stating of an account at that time is not possible, an accounting by such fiduciary in military service shall not be a prerequisite to the appointment of a successor fiduciary, and upon the reinstatement of such fiduciary or at such time as the said court deems meet, such fiduciary may be required by said court to file an accounting of his administration of the trust fund.