I was wondering about that, Roger!
Bexhill is a in a fabulous area for salty sea winds etc., and I can only assume that if you're on a plot next to lots of others, or even near them - the blight takes no prisoners!
I don't see how you could have brought the virus in! A chum just a few yards down the road from us lost everything too, and we're well inland! I have to inspect our plants every few hours!
Had there been less interference from the EU, we might have had a chance to buy something to alleviate the loss, and maybe more good people would have seen a result from what has been a misreable summer so far! Might be worth investigating alternative methods to control blight next year? I use soluble aspirin and it seems to work.
You certainly sound like an established gardener, and are therefore used to some crop failures, but that happens to all of us some years, and this year is no exception as it's been a rotten one!