@Foradada Angrill, Oriol Thank you for your patience!
The current backup solution for blobs is operational, which means the backup data isn’t stored in the vault but remains in the source storage account. Thus, the storage redundancy of the vault does not have any bearing. More importantly, using Azure Backup does not incur any additionally charges other than those due to blob point-in-time restore, additional data stored in the storage as versions, change feed etc., i.e., capabilities on which the operational backup solution relies- more details on this here.
Hope this helps!
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