3(1)In paragraph 2 above "relevant contract" means a contract which is entered into.—
(a)if the price formula specified in the election is derived from an actual contract which is identified in the election and was entered into not more than two years before the date of the election, at the time at which that contract was entered into, and
(b)in any other case, at the time of the election in question,
and which incorporates the terms specified in sub-paragraph 12) below, but is not necessarily a contract for the sale of ethane for petrochemical purposes.
(2)The terms referred to in sub-paragraph (1) above are—
(a)that the ethane is required to be delivered at the place in the United Kingdom at which the seller could reasonably be expected to deliver it or, if there is more than one such place, the one nearest to the place of extraction ; and
(b)that the price formula may be varied only in the event of a substantial and lasting change in the economic circumstances surrounding or underlying the contract and that any such variation may not take place before the expiry of the period of five years beginning on the date of the first delivery of ethane during the period covered by the election.