4.—(1) A licence-holder is a participant in relation to a phase if—
(a)the licence-holder or, where the licence-holder is a member of a group, the group—
(i)supplies 300 gigawatt hours or more of electricity in the qualification year for that phase; and
(ii)supplies electricity or gas to 150,000 or more domestic customers at the end of that qualification year;
(b)the licence-holder or, where the licence-holder is a member of a group, the group—
(i)supplies 700 gigawatt hours or more of gas in the qualification year for that phase; and
(ii)supplies electricity or gas to 150,000 or more domestic customers at the end of that qualification year; or
(c)in the case of phase 2, 3 or 4, the licence-holder was a participant in relation to the preceding phase.
(2) Where a dual licence-holder is a participant by virtue of paragraph (1), that licence-holder is to be treated under this Order as two participants, of which—
(a)one is a participant in respect of the supply of electricity; and
(b)the other is a participant in respect of the supply of gas.
(3) For the purposes of this article—
(a)whether or not a licence-holder is a member of a group is to be determined according to whether the licence-holder was a member of a group at the end of the qualification year for the phase in question; and
(b)where a licence-holder is a member of a group, the amount of electricity or gas supplied by the group in a qualification year is the amount supplied in that year by all licence-holders in the group, whether or not they were members of the group throughout the whole of that year.
(4) For the purpose of determining the number of domestic customers of a licence-holder under this Order, a domestic customer who receives electricity and gas from a dual licence-holder is a separate domestic customer under each licence.
(5) In this article, “dual licence-holder” means a person holding a licence under section 6(1)(d) of the Electricity Act 1989 and a licence under section 7A of the Gas Act 1986.