Lounge at D is for Thai passengers only. No Star Gold admitted. Not even with a C boarding pass? Keeping the UAL rifraf out? UAL needs to clarify/resolve. As I was boarding I commented in passing to Senior appearing gate agent who seemed concerned and actually followed me down the boarding corridor to tell me it was not open in time for UAL passengers. By the time I hiked at UA invitation to E and checked Louis Tavern out it was time to board so I could not personally check out the D Thai Lounge which I had used twice before. I felt I had been had by the engraved invitation.