Hello Elle,
Is this for a specific auditing scheme or standard? If so, I would suggest you review the requirements for rework control and product release and write up your SOP's for both that meet the requirements and your process. Suggestion...try to keep it as simple as possible. The more complicated it gets, the harder it will be to follow and less likely it will be followed no matter how much training you conduct.
Things to watch out for with rework...allergen cross contact, material is safe and suitable for rework (has been through a QA check of some kind and this is documented), lot traceability of the rework, a product break with rework (not continually reworking material into the same product over and over).