We're very sorry, but it unfortunately is not possible to add anything to a Private Warehouse shipment, including automatic Private Warehouse shipments.
Only items that have been in Private Warehouse for longer than 60 days are automatically shipped. Items that have been there 60 days or less are not grouped with them for the automatic shipment.
To have more items ship together, you would have needed to create a Private Warehouse shipment combining those items before the oldest item reached the 60-day mark. As our Private Warehouse Weekly Status Reports e-mails explain:
"Please note that items can be stored in your Private Warehouse for up to 60 days. Prior to the limit, you're welcome to to group items for shipment any way you wish, but if 60 days are exceeded, the items over the limit will be shipped to you automatically."
If you make a mistake in creating a Private Warehouse shipment, we can manually cancel the shipment for you (contact us) if the oldest item was in Private Warehouse 53 days or less and the shipping cost has not yet been paid.
A Private Warehouse shipment cannot be altered if any of its contents were in Private Warehouse longer than 53 days, or if it is an automated shipment of items in Private Warehouse longer than 60 days. In these cases, the shipment can either be shipped, or cancelled and its contents returned to stock for store credit of 85% of the item amount.