For a customer to receive event notifications when their unbilled usage balances reach, go above, or go below specified threshold percentages, you must configure the Unbilled Usage Threshold Adjustment Percentage setting.
For example, if you set the Unbilled Usage Threshold Adjustment Percentage client setting to 80%, you could send a customer an email notification when their unbilled usage balance is greater than, less than, or equal to 80% of the customer’s assigned unbilled usage balance threshold.