This section applies where a person ("P") enters into a contract under which—
P is not regarded as acquiring any chargeable interest by reason of entering into the contract.
If the contract is substantially performed without having been completed, this Part has effect as if the substantial performance of the contract were the completion of the acquisition provided for by the contract.
Accordingly, where subsection (3) applies and the contract is subsequently completed by a conveyance, that completion is not treated for the purposes of section 102 (taxable value) as effecting the acquisition of a chargeable interest.
Where subsection (3) applies and—
this Part has effect as if P had at the relevant time disposed of the chargeable interest referred to in subsection (1)(a).
In subsection (5) "the relevant time" means—
Where subsection (3) applies and the contract is afterwards varied (or partially rescinded) so that the chargeable interest to be acquired under the contract is not the same as the chargeable interest to which the contract originally related, this Part (including subsection (3)) has effect as if the variation of the contract effected—
If the parties to the contract proceed as if they had varied the contract in the way mentioned in subsection (7) (without actually doing so), subsection (7) applies as if they had actually made the corresponding variation in the terms of the contract.
In this section—