Internal Requisition with item serial controlled in Source Organization and no serial control in Des

 We have an issue where we shipped out an item with serial control from org1 and received in an Org2 with no serial control. we shipped out all the items from the org2 as no serial control. Now we wanted to change the serial control of the item in org2 to serial at receipt. What will happen to those serial that are in still in 'In-Transit' status. The reason why I m asking is we would potentially be receiving those items back in org2 via RMA in future and I cannot receive those serials which are physically present in the