The OurLocality backup regime is based on a daily snapshot of all files and database. The backup is incremental, so we can go back in time to some extent. The backups are archived on another physical disk so there should be 2 copies, should one go up in smoke/melt.
I am guessing you’re being pestered by the nice people behind JetPack to buy into their package. I’m not even sure this would work in the multisite setting that we operate.
Remember that the service we offer is on an as is and best efforts basis. Remember that it is possible to export your files and reimport them to another instance of your site somewhere safe, if you needed an archive copy.