12Where, in the case of any settlement made before 9th July 1958, any income arising under the settlement would, by virtue only of section 674, fall to be treated as the income of the settlor and not as the income of any other person, it shall not be so treated if —
(a)no power by reason of which it would fall to be so treated has been exercised after 8th July 1958, or is or can become exercisable after 5th April 1959, or such later date as the Board may in any particular case allow; and
(b)neither the settlor nor the wife or husband of the settlor has received or is entitled to any consideration or benefit in connection with the fulfilment of the condition set out in paragraph (a) above.