HMRC have updated their guidance Get tax relief on exported and converted components for Plastic Packaging Tax.
“Guidance has been updated about when you can claim tax back as a credit on your return, if you’ve paid tax on components. The example of claiming a credit when components are later converted by another business has been updated to reflect the new rate of tax as of 1 April 2023.”
https://www.gov.uk/guidance/claim-a-credit-or-defer-paying-plastic-packaging-tax