Found oil on the floor..... yet more! It was inside and just to the rear of the front RH wheel. After much faffing around, I eventually found the bottom of the (6 month old) master cylinder soaking wet. The pipes to it were dry. Couldn't figure it out and was beginning to wonder if it was a porous casting. After laying on the wing with my head in the engine bay (we do have to adopt some athletic positions with Land Rovers, don't we?) I could see fluid escaping from the joint between the reservior and cylinder. Wiggled the reservior and out it came.
So is seems I managed to break the reservior when I was fixing something else 'down in the depths'.
Ho hum. Something else to fix. :(