By receiving the first bill I found out that their figures are totally cocked up. Another company to chase – bring ‘em ON!

Rang them today. A very helpful bloke over the ‘phone helped me to bring in the real readings and confirmed that the old readings were in fact not “C” – customer readings, but “E” – merely estimates. This made sense instantly.

Also I’ve changed tariff to one more suitable for me. Shouldn’t save too much but at least, will definitely pay less for my electricity.

My landlords, BTW, happen to get some £40 refund. ;-)