27. References in this Part to an existing process are to a process—
(i)which was being carried on at some time in the 12 months immediately preceding the earlier date mentioned in paragraph 25 in relation to the description of processes within which the process falls; or
(ii)which is to be carried on at a works, plant or factory or by means of mobile plant which was under construction or in course of manufacture or in the course of commission at that earlier date, or the construction or supply of which was the subject of a contract entered into before that date.