public function add_30_minute_cron_interval($current_schedules)
{
// Only add the 30 minute interval if it wasn't already set.
if (!isset($current_schedules['minutes_30'])) {
$current_schedules['minutes_30'] = array('interval' => 30 * MINUTE_IN_SECONDS, 'display' => 'Every 30 minutes');
}
return $current_schedules;
}