To echo jonlea’s point about 7/10 hours… the offpeak times are programmed directly into the meter, the supplier doesn’t have any control over setting these times. So your E10 meter will record TEN hours of your electricity usage against the ‘offpeak’ rate. You give your supplier the ‘offpeak’ meter readings and they bill you accordingly.
You will always get TEN hours offpeak, regardless of whether the supplier wants to bill you for seven or gives you an E7 tariff.
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