/**
  * Retrieve list of files to be harvested, filter by date
  *
  * @throws Exception
  * @return string[]
  */
 protected function retrieveFileList()
 {
     $list = parent::retrieveFileList();
     // Take only the latest file
     if ($list) {
         $list = [array_pop($list)];
     }
     return $list;
 }