[Andreas]

Well, your request was "for 3 weeks ONLY.", so the Plugin exactly implements this
If you want "for up to 3 weeks ONLY", use this Code instead:

PHP Code:

function my_convert_date_to_timestamp($period)
{
    $p = explode('_', $period);

    if ($p[0] == 'P')
    {
        $time = 0;
        return 0;
    }
    else
    {
        $d = explode('-', date('H-i-n-j-Y'));
        $date = array(
            'h' => &$d[0],
            'm' => &$d[1],
            'M' => &$d[2],
            'D' => &$d[3],
            'Y' => &$d[4]
        );

        /*if ($date['m'] >= 30)
        {
            $date['h']++;
        }*/

        $date["$p[0]"] += $p[1];
        return mktime($date['h'], 0, 0, $date['M'], $date['D'], $date['Y']);
    }
}


if ($_REQUEST['do'] == 'dobanuser' AND my_convert_date_to_timestamp($vbulletin->GPC['period']) > (TIMENOW+1814400) AND !($permissions['adminpermissions'] & $vbulletin->bf_ugp_adminpermissions['cancontrolpanel']))
{
    print_stop_message('no_permission_ban_users');
} 


The Code you have to put in Hook mod_index_navigation depends on what you want to do, therefore I can't tell.

There is no "SMod CP" - just a ModCP that can be accessed by Moderators, Supermods and Admins.