My father got a similar letter, and he had been with the RAC for a very long time. I asked him how old he was, and he said 90. Whilst not saying so, that was the obvious reason, so I rang Churchill, with whom he had house insurance, and they covered him straightaway, and the premium was very reasonable too. Eventually, though, he did give up driving and said to me, "I'm not "with it" any more".