I am trying to add a new Payment method to the Payment API. I found the article here
https://vborg.vbsupport.ru/showthread.php?t=125369 by hambil, and it has been incredibly helpful, but I think I may need a little bit more information.
I'm planning to write a mod for USAePay, which supports recurring billing. I'd like to take advantage of the recurring billing when I create my plugin/hack, but I don't know how vbulletin checks to make sure a subscription is ongoing...does it wait for a postback from USAePay to find out if the subsequent payments are successfull / fail ? Does it make a request to a page on their site? Which PHP files contain this information?
Any information anyone could give me would be really helpful.