EngineGP/system/library/cron/users_recovery_signup.php

<?php
    if(!DEFINED('EGP'))
        exit(header('Refresh: 0; URL=http://'.$_SERVER['SERVER_NAME'].'/404'));

    class users_recovery_signup extends cron
    {
        function __construct()
        {
            global $sql, $start_point;

            $time = $start_point-86400;

            $sql->query('DELETE FROM `signup` WHERE `date`<"'.$time.'"');
            $sql->query('DELETE FROM `recovery` WHERE `date`<"'.$time.'"');

            return NULL;
        }
    }
?>