code: protected void checkAscpThreshold() {
  
  		if (TransferListener.getAscpCount() >= asperaTransferManagerConfig.getAscpMaxConcurrent()) {
  			log.error("ASCP process threshold has been reached, there are currently " + TransferListener.getAscpCount() + " processes running");
  			throw new AsperaTransferException("ASCP process threshold has been reached");
  		}
      }
docs: Check if ascp count has hit limit
  If it has throw an exception