That's right. All three registers on your meter have been assigned the same rate so that it simulates a flat rate tariff, even though the system thinks you have a multi-rate tariff. It's a bit of a hack, but it does the job and gets the intended result. Please make sure to submit the correct reading for each register though, so that your bills are correct.

If you end up upgrading to a smart meter, this hack/workaround can be removed and you can be placed on a proper single rate tariff for the future.
Just another guy passing by... The unknown tech way...
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