wp_get_archives custom function broken since upgrading to WP 3.7.1

I’ve upgraded a site I’m working on to the latest WP, but it appears the function I wrote for splitting wp_get_archives() into years is now broken and I can’t find out why. I’ve turned on debugging, but not getting any errors.

Can anyone see what’s wrong please?

Class OSUYMArchives
{
    public static function init()
    {
        /*-----------------------------------------------------------------------------------------------*/
        /* GET MONTHLY ARCHIVE DIVIDED TO YEARS */
        /*-----------------------------------------------------------------------------------------------*/
        /*
         * splits:
         * <h3>$Year</h3>
         * <ul>
         *      <li><a>$MonthName</a> $Number posts</li>
         * </ul>
         */

        function get_by_year($sql, $args) {
            global $wpdb;
            return $sql .= $wpdb->prepare(" AND YEAR(`post_date`) = '%s'", $args['year']); // modify the sql query based on year
        }

        function osu_ym_archive() {
            $archiveString = wp_get_archives('type=yearly&echo=0');

            // Find our strings to match
            preg_match_all("#title='(d{4})'#", $archiveString, $matches);

            foreach ($matches[1] as $year):
                echo "<h3>" . $year . "</h3>";
                add_filter('getarchives_where', "get_by_year" , 666, 2);

                // Set args for new wp_get_archives();
                $args = array(
                    'type'              => 'monthly',
                    'echo'              => 0,
                    'before'            => '<span class="cs-color">• </span>',
                    'show_post_count'   => 1,
                    'year'              => $year
                );
                $monthlyArchives = preg_replace('#(.+)(sd{4})(</.+>)#', "$1 $3", wp_get_archives($args)); 

                // Add span with class to post count numbers
                $monthlyArchives = str_replace( '(', '(<span class="cs-color">', $monthlyArchives );
                $monthlyArchives = str_replace( ')', '</span>)', $monthlyArchives );

                // Spit out monthly archives
                echo "<ul>" . $monthlyArchives . "</ul>";
                remove_filter('getarchives_where', 666);
            endforeach;
        }
    }

} // End OSUYMArchives Class

// Load Class
OSUYMArchives::init();