I just flew LAX-YVR on AC (with an AC flight number). Sadly, I was on a Tango fare, so of course they would not let me get an advance seat assignment without paying for it (fat chance!). I had my UA MP number entered into the itinerary. Even though I am a 1P, my boarding pass showed me as a Star Silver. I had a testy exchange with the woman working at the LAX Maple Leaf Lounge. She said I couldn't come in because I was only a Star Silver. I then showed her my (2004) 1P card, and she said sorry, that card has expired, it's from last year, so you still can't come in. Rolling my eyes, I then turned the card over and showed her that the status was good until February 28th. She then said, "oh" and reluctantly let me in. I find it very hard to believe that she didn't know this. I'm sure I'm not the first UA flyer that has tried to get in there...