Hello @Paul Simcox
Thank you for reaching out to the Microsoft Q&A platform. Happy to answer your question.
For Azure workload, it is the soft-delete feature that protects the data under undelete option from accidental deletions. For on-premises workload it is the security feature that needs to be enabled which helps in retaining data for 14 days, in case of deletion with the intent not retain data as described in this document.
To answer your question, for MARS agent backups, in order to get the undeleted data, you need to re-enable backup.
- Ensure you have the Security Feature is enabled on the Azure portal for the Recovery Services vault. This setting is under Recovery Service Vault->Properties->Security Settings
- You are making use of this feature in case of "Stop protection and delete backup data"
Hope this helps!
If you have any questions at all, let us know in the comments.
If the answer provided by has helped, please 'Accept as Answer' and Upvote using "Thumbs-up" so that it can improve discoverability for others in the community looking for help on the same topic.