I use the Billing API to create recurring charges based on time and based on usage
I saw that there are webhooks for when the subscription is updated
Is there a webhook topic that lets you know when a charge has been created and the user has been charged for my shopify app for the given subscription interval (30 days interval) or how do I know when an invoice for the subscription interval has been created
At this time, there are only a limited number of webhooks for updates to app charges as you mentioned. Generally, apps don’t have store permissions for being notified when an invoice is issued. I can certainly understand how it would valuable to know a merchant’s billing cycle, and I’ll be sure to let our product team know as well.