src/Marando/AstroDate/Traits/FormatTrait.php
private function formatO(&$str) {
    if (strstr($str, '%O')) {
      $o   = $this->timezone->offset;
      $os  = $o >= 0 ? '+' : '-';
      $oh  = sprintf('%02d', abs(intval($o)));
      $om  = sprintf('%02d', abs($o - intval($o)) * 60);
      $ofs = "{$os}{$oh}{$om}";
      $str = str_replace('%O', $ofs, $str);
    }
  }
private function formatO(&$str) {
    if (strstr($str, '%O')) {
      $o   = $this->timezone->offset;
      $os  = $o >= 0 ? '+' : '-';
      $oh  = sprintf('%02d', abs(intval($o)));
      $om  = sprintf('%02d', abs($o - intval($o)) * 60);
      $ofs = "{$os}{$oh}{$om}";
      $str = str_replace('%O', $ofs, $str);
    }
  }
Difference to UTC in hours
@param type $str