eBay GetSellerTransactions returning OrderID after single item shipped

[rob.9876]

We have noticed the Trading API GetSellerTransactions is returning orders that are shipped with an Order ID hours after originally returning the order without an OrderID. Why is this occurring?

We get the orders and they marked as shipped so returning the shipped orders is causing confusion. We combine single item orders into containing orders so now that the Order ID is eventually returned, a combined order of a single item trasanction is created.

If eBay are returning Order IDs for all orders, why is it not being set when the orders are originally returned to us?

[rob.9876]

Just in case anyone had a similar issue, it looks like the order id was added to the orders and the lastmodified date had updated making the orders available in the XML response. We were able to prevent the order being duplicated, picked up and dispatched again/refunded by checking the ShippedTime field in the XML and only allowing non-shipped orders to enter the system. The OrderID appears to be being set on the orders again now.