When an invoice is set up and the Enable Auto Pay box is checked the payment will be taken on the due date (if a single transaction) or on the day/date chosen in the Recurrence dialog.
Setting Up Auto Payments
The 'Create Invoice' screen now includes an 'Schedule for Auto Payment' option. Once selected, select a saved card (or enter a new card) to associate a payment source with the auto Payment. "Set Recurrence" functionality remains unchanged- the whole series of invoices will have autopay enabled on them.
Note that the due date must be at least one calendar day in the future.