How can we bring WO to unreleased status to delete an OSP operation from a released work order

Summary: we have a situation wherein standard discrete work order has been converted in released status with OSP operation, and this OSP was already executed in legacy application. Work order has been transacted in oracle. Now, there is a need to delete or skip OSP operation in Oracle. Release status does not allow any change to existing operations as we already know. Question comes what can be done except executing these OSP operation in Oracle?

Content (required): All transaction performed on work order operation have been reversed and work order 1st operation is back to "Ready" status. We tried to change work order status to unreleased from released it and gives error notification: "Updating the work order status from Released to Unreleased is not allowed transaction or pending transaction against work order exist. You may need to purge the in process records and try to update work order status again. Check if there are any records for corrections being processed by import process."