Domestic customers are the last people who would be affected by any supply issue that was likely to result in blackouts. IIRC there is a legal requirement for national grid to keep domestic customers lights on and homes heated as long as possible in the event of supply issues - in the event of blackouts they have to cut off industrial customers first to maintain supply to domestic ones.
This article is just about NG trying to get agreement with some of their customers that their supplies will be suspended during the winter peak demand period (basically when the majority of people get home from work and start ramping up energy consumption to do things like cook dinner (or tea, whatever you want to call it
). That and the amount of money they made which is perhaps a bit harder to justify.
