code: public function loadEndTime($value, Contao\DataContainer $dc)
  	{
  		$return = strtotime('1970-01-01 ' . date('H:i:s', $value));
  
  		// Return an empty string if the start time is the same as the end time (see #23)
  		if ($dc->activeRecord && $return == $dc->activeRecord->startTime)
  		{
  			return '';
  		}
  
  		// Return an empty string if no time has been set yet
  		if ($dc->activeRecord && $return - $dc->activeRecord->startTime == 86399)
  		{
  			return '';
  		}
  
  		return strtotime('1970-01-01 ' . date('H:i:s', $value));
  	}
docs: Set the end time to an empty string (see #23)
  
  @param integer              $value
  @param Contao\DataContainer $dc
  
  @return integer