I recently moved house and was very surprised to experience Scottish Hydro taking final bill amounts out of my account in the early hours of Christmas eve morning. The total involved was £560!!! I have of course intercepted and prevented those transactions from being completed.... On closer inspection (actually looking at my paperless bills..... I know, I know......) I find that my monthly payments more than covered my usage, confirmed by the fact that they reduced my monthly payments in Jan '15. Both my accounts were in credit at this point..... Billing changed to 6 monthly upon reading my July '15 bill, I'm a bit confused.... The total for this period was £485.23.... My payments totalled £156.... obviously from then on my debt to Scottish hydro has just grown and grown as my payments aren't covering my usage.... What I cant understand is - Why didn't they inform me and change my payments (as they had done in the January)? I have been presuming that I have been paying for my gas/electric as I've been going along... My other irk, is that the bill states they will collect the total "on or soon after 29 December 2015" so sneakily taking it in the middle of the night on Christmas eve is a little more than cheeky - My contracted DD date is 3rd of every month, so why the change in date for this payment?!!! Would just like to know if anyone knows if there is anything governing payment amounts and if companies must make sure consumer usage is kept up to date to avoid situations like mine..... many thanks