in 3.0.x-and-above/upload/catalog/controller/extension/module/facebook_business.php [574:588]
private function getSpecialPricePeriod($product_info) {
if (!empty($product_info['special']) && $this->config->get('module_facebook_business_sync_specials_status') && !empty($product_info['special_date_start']) && !empty($product_info['special_date_end'])
&& $product_info['special_date_start'] != '0000-00-00' && $product_info['special_date_end'] !='0000-00-00') {
$datetime_start = new DateTime($product_info['special_date_start']);
$datetime_end = new DateTime($product_info['special_date_end']);
$special_date_start = $datetime_start->format('Y-m-d') . 'T00:00+00:00';
$special_date_end = $datetime_end->format('Y-m-d') . 'T23:59+00:00';
$special_price_period = $special_date_start . '/' . $special_date_end;
return $this->formatAndTrimString($special_price_period);
} else {
return '""';
}
}