I have been in and out of LHR often this year, and have been using the SQ Silver Kris Lounge instead of United Club. It is often quiet and offer better food and beverage.

I know LH, OS, LX and SN direct their passengers to the LH lounge.
AC does it for its Maple Leaf Lounge and UA agents have been directing us to the United Club.

I wonder which lounge(s) CA, BR, TG, NH, MS. TK, ET., OZ are directing their business and *G passengers to.
I did LHR-TPE and :LHR-PEK prior to Covid, and was directed to use United Club by CA and BR check-in agents. In both cases, I went to SQ lounge instead.