I have a web operated tariff. The energy company is obliged to read the meter infrequently, but the rest of the time I need to submit readings.
If consumption deviates from the norm, the monthly direct debits are adjusted to ensure they meet the anticipated annual bill.
I am ahead in the summer months as to be expected, but overall the monthly payments are accurate.
On occasions where there has been a price rise, there has been an estimate of the consumption at the old rate and at the new or I've been advised to submit a meter reading to produce a more accurate bill.
All told, nothing to complain about.