Nelio A/B Testing will send notifications to the e-mail provided when you registered to the service. In addition to it, you can specify another email address for notifications through the Settings of the plugin:

Furthermore, if you hold a Professional Plan you can specify if you want to be notified when an experiment is automatically stopped (because it achieves a number of page views used, it reaches the significance level you want, and more...). Just confirm this by going to the Advanced tab in the Settings of the plugin and selecting this option.