Michael,

I have to somewhat shamefacedly admit that only while googling around after posting that did I discover that is what R.A.O.B. meant....

I certainly should have known better, as my maternal Grandad was one at one time, it seems, though certainly not actively so. He had a Membership Scroll (which we found after his death) but my Mum didnt remember any real mention being made of it, though recalled that he had been one.