Hi MSTolchard,
Great question!
Your smart meter records your usage data in 15 or 30 minute intervals, and then uses the intervals between date X and and date Y (as listed on your bill) to calculate your consumption for this period. If data is unavailable for even one of these 15/30 minute intervals for whatever reason, then your bill will read as estimated as we have no way of knowing for certain precisely how much power was used for this period.
With this in mind, it's conceivable that just one or even a few intervals are unavailable, so your bill may still be very accurate despite being 'estimated'. If you'd us to clarify which periods have been estimated, please feel free to get in touch with our customer service team by following the prompts here.
Kind regards,
Jayden
