The group will now join the first wave of electricity suppliers, alongside Eastern, Yorkshire and Seeboard, which are able to offer customers the choice of supplier when the market opens on 1 April 1998. Offer is expected to announce ScottishPower's accelerated timetable later this week.
The group has told Offer it is moving the testing of its new computer systems from January 1998 to October this year. The change means that plans to start competition in its regions next May have been brought forward to April.
The improvement affects the group's 3 million customers in the southern half of Scotland and in Manweb, its regional electricity subsidiary in North Wales and the North West. Competition is being phased in by postcode area, with customers in Motherwell among the first to be able to choose alternative suppliers.
Under rules drawn up by Offer, ScottishPower will now be allowed to compete for customers in the areas opened up by the three other power companies in the first wave. Because so many regional electricity companies have been unable to introduce competition on time, Offer has banned latecomers from competing in opened-up regions until their own systems have been successfully introduced.
The other three electricity groups in the first wave were already planning to exploit their advantage by marketing in other areas. ScottishPower wanted to join the early starters,after its aggressive attack on the emerging domestic gas market.