I noticed today when I was checking my numerous up and coming itineraries that one had in red an update for me. When I looked I found that on the trans atlantic segments that the aircraft had changed, it was a B767-400ER and now was changed according to UA to an Airbus A330-300. What? since when did UA have such and aircraft. After agreeing to changes and then looking at the itnerary once again, there it was B767-400ER not an A330-300, how in the world would UA even be able to show an A330-300 when they don't have them?