Limited resources on the hub. It is up to you to setup a procedure to offload backups, same with any other system.
This does bring up an opportunity to improve the backup/restore experience. An option could be added to mark a backup as read-only which would not be overwritten. It would be up to you to flag it. I have no idea if they would even consider implementing something like this. I'll submit a feature request. Another option would be to also include a 30 day backup in the schedule. Where would it end? Ultimately it is up to you to keep copies of your backups.
