A glitch in the way an energy company computes bills resulted in a shock for one poor lady, who was greeted by an automatically generated demand for an extra £13,230.55.
Rob did the right thing. When his mother received an estimated bill showing the company thought 7328 units had been used, he went online and gave Southern Electric an accurate reading from the meter, which was lower, and stood at 7305.
But instead of subtracting 23 units from the total, Southern's online calculator assumed the meter had been "clocked" and had risen past 9999, reset itself, then gone all the way back up to 7305. And as the lady had not been inflating hot air balloons in her garden, this was obviously not the case.
Southern told The Register the glitch came about because users have a two-week window after receiving a bill to enter a lower figure. After two weeks, the system assumes your bill will have risen, so the online calculator goes up, and if necessary, all the way back around again.
So if your direct debit is £10k or so per month higher than you might reasonably expect, there could be a refund in it for you. [Register]