TOPIC: do I need to fill-in custom email

I found your awesome plugin and installed it in my three joomla sites. Do I need to specify the custom email address or will the plugin default to a superuser email?
Thanks

If you've set the option to mail to admins to true, then all admins on the site should get a mail.

Regards,
Daniel

I noticed that On one if my sites I do not have the "notify user groups" set and the "send to custom email address" is also empty. Would this prevent any update notifications?