Keep multiple files backup snapshots, even if they are all taken in the same day

[t-m-w]

If multiple files backups occur and we still haven't exhausted our maximum number of backups, then go ahead and keep more backups, even if it's during the same day. This would be useful for security reasons.[citation needed]

Currently, if you start fresh with files backup, and you run "Backup now" multiple times in a row, there will only ever be a single files backup preserved, when run during the same day.