(1) That where an interest limited to cease on a death (within the meaning of section 30 of the Finance Act, 1941 (No. 14 of 1941) has, after it has become an interest in possession, been disposed of or has determined either wholly or partly, then, whatever the nature of the property in which the interest subsisted, the following persons shall be accountable for any estate duty payable on the death by virtue of that section (in addition to any persons accountable therefor apart from the provisions contained in this paragraph):
(a) if the settlement under which the interest subsisted is in existence at the death, the trustees for the time being of that settlement, and
(b) if it is not, the persons who were the last trustees of that settlement.
(2) That the provisions contained in the foregoing paragraph shall have effect only in relation to deaths occurring after the passing of the Act giving effect to those provisions, whether or not the relevant interest is disposed of or determines after such passing, so however that no person shall by virtue of those provisions be accountable as trustee of any settlement for any duty except to the extent of the property comprised in the settlement after such passing.