I was tempted to try this morning but decided not to. At check-in today the lady in front (flying to CAI) was directed to the new lounge. For me, I was explicitly told to visit the 'Gate number 2 lounge' (probably the first time thats been mentioned in such terms) and had a big number 2 written on my boarding card too....

LHR has new signs up now pointing to the new lounge, and the signs explicitly say "International departures only" vs "domestic departures only" for the Gate 2 lounge.

I guess I'll let someone else prove the way, or otherwise, and try, on a domestic flight , but I am also very tempted to wait as was looking for an excuse to visit the Middle East with BMI, so, getting to visit this lounge whilst doing it will hopefully be the added incentive/a little different (as well as a chance to get rid of some GUVs), and I'm a patient guy