12(1)The amendments made by paragraph 8 do not have effect in relation to—
(a)any transaction that is effected in pursuance of a contract entered into and substantially performed on or before 16 March 2005, or
(b)(subject to sub-paragraph (2)) any other transaction that is effected in pursuance of a contract entered into on or before that date.
(2)The exclusion by sub-paragraph (1)(b) of transactions effected in pursuance of any contract entered into on or before 16 March 2005 does not apply if—
(a)there is any variation of the contract or assignment of rights under the contract after that date,
(b)the transaction is effected in consequence of the exercise after that date of any option, right of pre-emption or similar right, or
(c)after that date there is an assignment, subsale or other transaction relating to the whole or part of the subject-matter of the contract as a result of which a person other than the purchaser under the contract becomes entitled to call for a conveyance.