Create Invoice Subscription

Let a customer whose card checkout failed pay by invoice instead.

Card checkout can be impossible rather than merely inconvenient: registering a recurring mandate in India requires a 3-D Secure challenge with the issuing bank, and when that bank's page does not respond the customer cannot pay at all, however many times they retry. Rather than leaving them to email us and wait out a timezone gap, this mints an invoice-billed subscription on the spot and Stripe emails them a payable link.

Nothing is granted by asking. The subscription reports itself active immediately, but invoice_billed_access_is_withheld denies the organization until a settled payment is recorded, so this is a request to be billed, not a way to obtain access.