Hello again pudding,
I've been taking another look at your photo, as I said I had doubts. I've took your photo and cleaned it up a bit, and in comparison to a couple others I have you will see that there is a marked difference. The building in you photo is only two storey whilst the junction was three.
As I said I can't think of anywhere else on Bloomsbury St it would fit, so unless anybody else has an idea I'm at a loss.
Phil