Where do I see scheduled prepaid orders?

When the subscription is renewed, a new order is created automatically in your shop.
However, with the pre-paid subscriptions, Shopify automatically creates a fulfillment schedule on the initial order. This means that you can see the scheduled fulfillments in Shopify Admin -> Orders -> filter by Fulfillment status by the value "Scheduled."
And you can see which orders you currently have to fulfill in Shopify Admin -> Orders -> filter by Fulfillment status by the value "Unfulfilled" and "Partially fulfilled."

We also recommend merchants to turn on the notification which will alert them about the upcoming scheduled order 24 hours before the scheduled date. You can turn this on in Seal Subscriptions > Settings > Notifications > turn on the 24 hours before the next scheduled fulfillment notification.