If the product Prorating Type is In Advance, In Advance - No Refund, In Advance - No Prorate, or In Advance - Future Disconnect, you can designate the number of charge cycles (from 1 to 12 cycles) to bill in advance.
Example
Your company charges for Voice Mail two months in advance. You set up Voice Mail with a charge of $5.00 on a monthly basis and your customers are billed on a monthly bill cycle.
A customer is in the bill cycle that bills on the first of each month. This customer adds Voice Mail on July 5th. The August 1st invoice includes:
$4.35 for the days in July that Voice Mail was in service
$5.00 for the month of August (1st month In-Advance)
$5.00 for the month of September (2nd month In-Advance)
The September 1st invoice includes:
$5.00 for the month of October (2nd month In-Advance)