All depends on what kind of "smart meter" you have. Mine with my rater plan needs a bit more than start reading date /time of reading end reading date/time of end reading....
But in the end - this is trying to make a mountain out of a molehill - the actual readings WILL eventually catchup.
The ones I feel sorry for are those who don't have a home any more.
Ours is read daily but sometimes a system glitch may cause them to miss daily readings.
But at the end of the month instead of an estimated bill they simply take the beginning and end of the month to calculate your bill, just like an ordinary meter reader would do.
The difference is that there are no humans to make mistakes writing down numbers , brave hostile environments, and waste fuel and time to read a meter.