protected function _update()
    {
        $this->_aSkipSaveFields = ['oxtimestamp', 'oxorderdate'];
        $this->oxorder__oxsenddate = new \OxidEsales\Eshop\Core\Field(\OxidEsales\Eshop\Core\Registry::getUtilsDate()->formatDBDate($this->oxorder__oxsenddate->value, true));

        return parent::_update();
    }