Deleting a backup set deletes the backup files
When a backup set is deleted from Rhinoback, all files are deleted from the backup storage system. Retention policies no longer apply and all of the older versions of files in the backup set are also deleted. Deleting an entire backup set will result in all storage used by the backup set becoming free and returned to the quota within a day.
Do not delete a backup set unless you are sure that you will not need to restore any of the backup files.