Where—
then, unless it is shown that the purchase of the annuity and the making of the insurance (or, as the case may be, the substitution or variation) were not associated operations, the person who purchased the annuity shall be treated as having made a transfer of value by a disposition made at the time the benefit of the policy became so vested (to the exclusion of any transfer of value which, apart from this section, he might have made as a result of the vesting, or of the purchase and the vesting being associated operations).
The value transferred by that transfer of value shall be equal to whichever of the following is less, namely,—
The preceding provisions of this section shall apply, with the necessary modifications, where a contract for an annuity payable on a person's death is after 26th March 1974 made or varied or substituted for or replaced by such a contract or a policy of life insurance as they apply where a policy of life insurance is issued, varied or substituted as mentioned in subsection (1) above.