If all items from an order were returned it's status will be changed to 'Returned'. In case of a partial return only an order will remain in 'Delivered' status.
When you transmit a new order for fulfillment to eWarehouse your customer will be sent an email with a link to an order-specific management page. The page allows your customer to check the order fulfillment progress, track it when its shipped and also request and expedite returns. After a return request gets submitted you will receive a notification email and will have to either approve or decline the request. Once approved an email will be sent by our system to your customer on your behalf with the return instructions.
This feature can be fully customized and enabled / disabled by you in your account or by us - just submit a support ticket.