The Billing Schedule tab

Billing Schedule shows Upcoming Billing Schedule — Manage automatic billing schedules and upcoming invoices

Each line is a subscription with Next: {{date}}, so "when does this customer get billed" is answerable without opening anything.

Generate Invoice Now raises the invoice ahead of its date. Use it when a customer asks for the invoice early, or when you are closing a month and want everything out before the cut-off. It brings the invoice forward; it does not create an extra one, so the schedule moves on rather than double-charging.

Modify Schedule and New subscription change what is coming.

Check this before month end. Two minutes here catches the subscription with a wrong next date or a missing amount, while it is still a settings problem rather than an invoice the customer has already received.

No upcoming billing scheduled — No active subscriptions with upcoming billing dates found. If you expected something here, the usual causes are that the subscription is set to manual invoicing (The Manual Invoicing tab), or that it has no next invoice date at all.

This tab is the plan; the billing dashboard is the outcome. What actually ran, and what failed, is monitored separately: Automatic billing runs.