For the purpose of apportioning the duty payable on the estate of a deceased person, any provision directed to be made by an order under this Act shall –

(a) if the deceased person died testate, be deemed to be a bequest made by the deceased person by a codicil executed immediately before his death; or

(b) if the deceased person died intestate, be deemed to be a bequest made by the deceased person as if effected by a will made by him immediately before his death.