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Depending on if you get monthly or quarterly billing will depend on when we need the readings, but you can actually upload your reading at any time to get a cost to date.
For monthly billing, just submit it the day before you get your bill issues. e.g. if your bill cycle is 15th-14th, then I would suggest submitting your read on the 14th for billing.
For quarterly billing, we will advise the time frame on the second page of your invoice below your metering information so you know exactly when to put it through.