New Handke novel (in German)

According to a German site (new to me) dedicated to Peter Handke, the greatest living Austrian writer had a new novel published last month. The title Kali: Eine Vorwintergeschichte is translated by publisher Suhrkamp as Potash: a Pre-Winter Story. It seems to have elements of the story of Austrian schoolgirl Natascha Kampusch. But the book description in Suhrkamp's comedy English makes it no clearer.