Hi @mij2020 - Thank you for contacting us!
By default an on-demand backup is retained for 30 days if triggered from Azure portal.
FAQ link - https://learn.microsoft.com/en-us/azure/backup/backup-azure-vm-backup-faq#does-an-on-demand-backup-job-use-the-same-retention-schedule-as-scheduled-backups
You can check the retention period for that ad-hoc backup if you go to backup jobs and click on this manual backup. You should see a field called “Recovery Point Expiry Time in UTC” which marks the date when the restore point (RP) will expire.
As for extending the expiration period for a manual RP, I don’t think that’s possible as this RP will not be influenced by the backup retention policy associated with the VM.
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