3 extra hours of cheap electricity each day - should I tell my supplier?

[TheEarthIsFlat]

Ok, not strictly true, we're getting the right amount of cheap electricity but at the wrong time. I got sent a monitor and put the washing machine, dishwasher & breadmaker to run overnight but found we weren't using any cheap units & was actually costing us more.

Turns out our meter's been set up wrong so Economy 7 runs from 3am to 10am instead of 12.30 to 7.30am. I can use this in my favour, so run everything at 3/4am & then boiling the kettle, doing an extra wash in the morning is saving us money, but am I being dishonest & will it cause problems later if I get caught out?

I'm guessing it's been like this for at least 2 years - when British Gas upgraded our meter to a digital one - but dp says it could even be decades because the dial that's got the wrong time has been untouched in all the time he's lived here. (It's the link to the mains, don't know the technical word, but the sort of thing that has
'danger of death' written on it.)

So, do I own up or do I play dumb, and would my supplier make me pay/pay me back if they found out?

In theory you've probably been getting overcharged for 2 years if your heating has been running at the more expensive time. Personally I would have thought you'd be in refund territory if you've been using things at a more expensive time in error, but electricity companies very rarely seem to give an inch even if it's their mistake.

It's their mistake and had you not got the monitor you'd never have known. You need the money far more than they do I'd wager, so I'd keep quiet