优化重定向代码

I found this from a shortcode and we're having a bit of an issue with the loading time using this function. I was wondering if there's a way to further optimize this or perhaps use a php redirection instead of javascript?

function gdp_mss_after_login() {
$user = wp_get_current_user();

if( $user && is_object( $user ) && is_a( $user, 'WP_User' ) ) {

    $user_level = get_user_meta($user->ID, 'gdp_level', true);

    ob_start();

    if ( !empty($user_level) ) {
        $post_id = get_option('gdp_mss_course_level_' . $user_level);
        $url = esc_url(get_permalink($post_id));
        ?>
        <script type="text/javascript">
            window.location = '<?php echo $url; ?>';
        </script>
        <?php
    }

}
return ob_get_clean();
}
add_shortcode( 'gdp_mss_login_redirect', 'gdp_mss_after_login' );