Recently I've experienced a VPS crash so it was time to use the backups.
Unfortunately, the contents of the backup file was 1 day older than its date. It didn't contain some information from the last day, although it was sent after already having that data in the database.
And all 4 or 5 backups I got into my e-mail at once, were the same.
I'm not sure whether this is a bug or not, just sharing.