PMPro-extra-expiration-warning-emails (Change day email is sent out)

pmpro-customizations.php

<?php
/*
Plugin Name: PMPro Customizations
Plugin URI: http://www.paidmembershipspro.com/wp/pmpro-customizations/
Description: Customizations for Paid Memberships Pro
Version: .1
Author: Stranger Studios
Author URI: http://www.strangerstudios.com
*/

function ts0325_fix_frequency($templates) {
//Code below will send out an email warning at 21 days.
	return array( 21 => 'membership_expiring');
}
add_filter('pmproeewe_email_frequency_and_templates', 'ts0325_fix_frequency');