Strangely none of the local shops (or Tesco) appear to have carried it, unless it was sold out quickly after release. I'll have to buy it online.
Perhaps they don't like stocking hardbacks? The paperback will be released on 2 June 2016.
However the HB has been reduced by £10 to £9.99, I can't imagine buying the kindle version for £9.45, though I'd maybe pay 50p extra to have it included with the hardback.