Yes, white suddenly seems all the rage for Series Ones seeking new owners. There's that lovely TC for £9450, as you say, plus a 3500 converted to manual which looks highly interesting, and two red-upholstered 200os with dealers both priced much higher than my car even though one is an auto. All are on Car and Classic. Both 2000s look very nice, but no more so than mine! And that's me being objective, not biased.
The fact that these high prices are being asked by dealers, even if they have not yet been achieved, suggests a move towards appreciating Series Ones for the rare and wonderful things they are. The P6 range has been underpriced for too long and managed to miss out on the classic market's surge a year or two ago, but maybe we're seeing the beginnings of an appreciation of them by a wider market and they will gain the higher value they deserve. If I sell mine it will definitely happen, because cars always seem to rocket in value just after I've sold them. Never before.