If I get customer's usage data 24-48 hours later when their CUR gets to their account, How can I send the metering record within one hour?

Hello from the AWS Marketplace Seller Operations team. One way of sending metering records every hour is to record a quantity of 0 if there is no usage to report for that hour. You can find further details in the metering for usage : https://docs.aws.amazon.com/marketplace/latest/userguide/metering-for-usage.html

Regarding the refund for incorrectly billed usage you can refer to the Software metering refunds section under this guide- https://docs.aws.amazon.com/marketplace/latest/userguide/refunds.html

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