@Override
 public void informInsertionEnds(Collection<VehicleRoute> vehicleRoutes) {
   List<VehicleRoute> routes = new ArrayList<VehicleRoute>(vehicleRoutes);
   for (VehicleRoute route : routes) {
     if (route.isEmpty()) {
       fleetManager.unlock(route.getVehicle());
       vehicleRoutes.remove(route);
     }
   }
 }