If you are currently splitting orders by section, and if one of the orders in the split only includes retail products, then the order will be treated as a retail order.

If the whole order is unpaid, then the retail order will be sent to the Ready page to ensure staff does not miss a payment for it later.

Otherwise, if the order is paid, the split order with just retail items gets treated as a regular retail order and set as completed, therefore it would get fully processed on the New Order page.