Just noticed on the mystatus.united.com page, for lounge access (I'm gold), it says:
Access to 1,000 Airport Lounges for you and a guest when you travel with any Star Alliance member airline — regardless of your class of travel1
1 Guests must enter with an eligible Star Alliance Gold customer and must depart on a Star Alliance airline, though not necessarily on the same flight. Status level benefits vary among frequent flyer programs.
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Now I'm WELL aware that it's always applied that, to get into the UA lounges, you needed to be travelling internationally or using a different *G card. But the way it is worded right now, does NOT exclude traveling on United. It explicitly says "any star alliance member" and the footnote does not exclude UA.