New Year reference resetting

$refline_placeholders = array(
    'MM' => 'date',
    'Y' => 'date',
    'YY' => 'date',
    'YYY' => 'date',
    'YYYY' => 'date',
    'UU' => 'user',
    'P' => 'pos',
//     FIXME:  for placeholders below all the code should work, but as the ref length is variable,
//       length specification in placeholder format should be implemented.
//    'C' => 'customer',
//    'B' => 'branch',
//    'S' => 'supplier',
//    'L' => 'location'
);

                        case 'Y':
                        case 'YYY':
                            list($begin_day, $begin_month, $begin_year) = explode_date_to_dmy(begin_fiscalyear());
                            list($end_day, $end_month, $end_year) = explode_date_to_dmy(end_fiscalyear());
                            $out .= $ph == 'Y' ? sprintf('%04d', $begin_year) : sprintf('%04d', $begin_year) . "-" . sprintf('%02d', $end_year % 100);
                            break;

function is_valid($reference, $type, $context=null, $line=null)
    {
         if (!isset($line))
             $line = $this->reflines->find_refline_id($reference, $type, true);

         if (!isset($line))
             return false;

        $refline = $this->reflines->get($line);

        if ($this->_legacy_line($refline))    //legacy non-templated line
            return strlen(trim($reference)) > 0;

        $regex = preg_quote($refline['prefix'].$refline['pattern']);
        if (!is_array($context))
            $context = array('date'=>$context);

         $context['pos'] = $_SESSION["wa_current_user"]->pos;

        if (is_date(@$context['date']))
        {
            list($year4, $month, $day) = explode("-", date2sql($context['date']));
            list($begin_year, $begin_month, $begin_day) = explode("-", date2sql(begin_fiscalyear()));
            list($end_year, $end_month, $end_day) = explode("-", date2sql(end_fiscalyear()));
            $year2 = substr($year4, 2);
            $year3 = $begin_year."-".substr($end_year, 2);
        } else
        {
            $month = '\d{2,}';
            $year2 = '\d{2,}';
            $year4 = '\d{4,}';
            $begin_year = '\d{4,}';
            $year3 = '\d{4,}-\d{2,}';
        }
        $cust = @$context['customer'] ? $context['customer'] : '\d+';
        $supp = @$context['supplier'] ? $context['supplier'] : '\d+';
        $branch = @$context['branch'] ? $context['branch'] : '\d+';
        $location = @$context['location'] ? $context['location'] : '[a-z0-9]+';
         $pos = @$context['pos'] ? $context['pos'] : '\d+';
        $user = sprintf("%02d", $_SESSION['wa_current_user']->user);

        $regex = preg_replace(
            array(
                '/\\\{/',    // unquote placeholders
                '/\\\}/',
                '/\{MM\}/',
                '/\{Y\}/',
                '/\{YY\}/',
                '/\{YYY\}/',
                '/\{YYYY\}/',
                '/\{C\}/',
                '/\{B\}/',
                '/\{S\}/',
                '/\{L\}/',
                '/\{UU\}/',
                 '/\{P\}/',
                '/\{\d+}/',
            ),
            array(
                '{',
                '}',
                $month,
                $begin_year,
                $year2,
                $year3,
                $year4,
                $cust,
                $branch,
                $supp,
                $location,
                $user,
                 $pos,
                '\d+',
            ), $regex);

        $regex = '"^'.$regex.'"i';

        return preg_match($regex, $reference, $match) ? 1 : 0;
    }