Mostly yes, Scotkat, but at gardening Scotland JBA Potatoes were selling one for planting now and harvesting in October. Try their web site: http://www.jbaseedpotatoes.co.uk/
If we had the space we would have tried some.

If you can't get Bu;baholiocs reccommended variety remember if you plant this late don't plant late or maincrop , plant earlies if you can get them, as they have a shorter growing season