Our legacy plans were billed post-monthly (on the last Tuesday of each month). WorldVia PRO bills on a pre-month basis (on the same day each month, whenever the switch takes place).
So what that means for your agents, is for example, if the charge goes through on Feb 6th for WorldVia PRO, that charge is for Feb 6th-March 6th. They might also see a charge on Feb 10th through ACH which would be for the month of January.