191. The provisions of sections 189 and 190 shall, so far as they can be made applicable, apply in the case of a person subject to this Act (not being an officer or ¹[master warrant officer or warrant officer]) who notwithstanding anything contained in the Lunacy Act, 1912, is ascertained in the prescribed manner to be insane, or, who being on active service, is officially reported missing, as if he had died on the day on which his insanity is so ascertained, or, as the case may be, on the day on which he is officially reported missing: Provided that in the case of a person so reported missing, no action shall be taken under clauses (2) to (5) of section 189 until such time as he is officially presumed to be dead.