Leucism (or is it xanthochroism) in Sparrows???

......anyway, were talking fawn coloured Sparrows! Here's a shot at the end of the one that was in Norman's garden at Valley a few years back. But more interestingly is a letter I came across recently relating to a bird I encountered in my back garden in St Helens in 1988.I wrote to BB with two photos of the bird but the letter I got back off BB could have put me off birding for life! Obviously unhappy with their reply I wrote to Birdwatching magazine and got back the answer I was looking for thankfully!