The developer decides to upgrade from free to paid plan of $200.Oct 20
The billing period on invoice would be Oct 1 - Oct 31. Within one day, invoices are generated by system and are kept in "finalized" state for provider to review.
The generated invoice is based upon pro-rata calculation on the remainder of the month i.e (11/30*200) = $73.33Oct 21
After two or three days, the invoices are issued to the developer.The provider can view the invoice state as "pending". Oct 24
After two days, the developers credit card is charged for the issued invoice.
The invoice state is in "pending" state unless the developer credit card is charged. As soon as it is charged, the state is changed to "paid"Oct 26