NetApp SaaS Backup
How many copies of data do we maintain with SaaS Backup for Office 365?
That depends on your policy setup - we provide three policies by default, backups every 12, 18 or 24 hours, and with retention for up to three years. So if you use every 12 hours, and three years, you would keep up to 2190 backups - https://docs.netapp.com/us-en/saasbackupO365/concept_backup_policies.html
Hope this helps!
Sorry, I should be more clear on my previous question. 😃
In fact what I am wondering about is whether the service store redundant data across AZs or even regions.
I bet yes but I was not able to find any documentation to testify that.