They tried to increase our direct debit from 150 to 450 a month. I called them to find out why and they gave me the standard... we read your meter and it was higher then previous estimates. Ok you cant argue with that, or can you? As we take both gas and elec from them, I asked them for the readings 12 months ago and then I read the meters today. I calculated given the pence per kwh for all the readings and worked out that we should pay about 130 a month, not 450 a month. They keep trotting out this real vs estimate sentence. Anyhow I then compared todays readings with the ones they took 3 weeks ago. They do not put these on the bill anymore. It turned out their reader had made an error inputted the wrong reading, so the bill for elec was 700 not 2000 as they had calculated. So if I was an old person, I would have just said ok, you read the meter, you must be right, I will find another 300 pounds a month. Unluckily for them I am not that old, have a science degree and am no stranger to electricity or KWH. To be fair the poor guy on the phone did his best and was nothing but polite, as was I. So be careful if you get any stupid bills and just question them in detail until its sorted.