The No-Checkout section tracks buyers who have mined an item but haven't completed their Seller Center checkout yet. NC tracking works on all plans — what differs is what actions you can take on each buyer.
Buyers in the No-Checkout section appear with an NC badge next to their name on the mine board. They're still being tracked — they just haven't paid yet.
When a buyer in no-checkout finally completes their Seller Center order, you can mark them as checked out from their row. Their NC badge is removed and they move out of the no-checkout section.
If a buyer is in no-checkout at the end of a session, they automatically become a carry-over for the next live. They appear on the mine board at the start of your next session with their Relive badge.