Hook um_before_email_notification_sending

um_before_email_notification_sending.php

<?php

/**
 * Hook: um_before_email_notification_sending
 *
 * Type: action
 *
 * Description: Fires before sending an email notification.
 *
 * @example https://github.com/ultimatemember/ultimatemember/blob/master/includes/core/class-mail.php#L408
 *
 * @package um\core
 * @see     um\core\Mail::send()
 * @since   2.0
 * @version 3.0
 *
 * @param string $email    Comma-separated list of email addresses to send message.
 * @param string $template Template key.
 * @param array  $args     Template settings.
 */
function my_before_email_notification_sending( $email, $template, $args ) {
	// your code here.
}
add_action( 'um_before_email_notification_sending', 'my_before_email_notification_sending', 10, 3 );