It's probably only a local store promotion. The website still lists it at ã15.
Of secondary interest I noticed whilst checking this that Tesco sell low alcohol Everyday Value Bitter and Lager for the princely sum of ã1.10 for 4 x 440ml cans. I'm sure the bitter is bad enough, but the lager can only be as bad as the home brewed lager I was offered in Saudi Arabia which has been made from non alcoholic Kaliber, table sugar, and fermented with bakers yeast.