Auto Update

If the auto update is enabled (ticked off), will UNA give an alert before updating. This is regarding the button at Studio > Settings > System > Site Settings > Enable auto-update. The point is that since there are problems even with the stable version, it seems that the site/database should be backed up before even an auto-update. Otherwise if the UNA updates behind the scene, there is the likelihood that the site may be converted into an error site permanently. I am curious about this.