As of Breview Pro version 1.x.x, an email gets sent to the customer once an order gets completed requesting the customer to submit a review.
Configuring Emails
You can configure the email settings from MS Web Arts -> Breview -> Emails. Right now, there is only one email trigger available that happens when the order gets completed. You can enable or disable sending this email by configuring the Review Request on Order Completion setting.
We are planning to add some advanced emailing options to improve the probability of capturing reviews.
For Advanced Users Only:
To edit the texts or make complete changes to the email content, you can navigate to /wp-content/plugins/breview/templates/emails/completed.php. Copy the file and paste it to /wp-content/themes/your-theme/breview/emails and make the changes as you want.
You can view the Overriding Templates documentation file to understand how to override the template files of Breview. Again, any file changes should be done by advanced users or a developer only. Otherwise, you may break the website.