To turn on/off email notices from automatic updates, you may use Send Report Email option available within Automatic Updates module.
This option helps you to control how you are notified of automatic updates that have occurred.
You can also specify who will, if you enable the option, receive email notifications when automatic updates are applied.
If you want to be notified from automatic updates, simply enable the Send Report Email option end enter email address into the Report Email Address field.
The upgrade reports will be sent to that email address. If this field is empty, it will default to the Site Admin email address:
To turn this option off, just click the slider to disable Send Email Reports option.