Billing: Card on File Before the First Invoice

New client billing starts by collecting a payment method, so the first invoice is not also the first time anyone finds out the card is missing. Cancelled subscriptions now drop out of the portal’s billing view instead of lingering.

• Card-first onboarding, with a persisted switch from external to Stripe billing
• Expired and cancelled subscriptions no longer show as live in the client portal
• External invoices can list what is included without printing a price against each line