The incoming boss of the Volkswagen Group, Oliver Blume, will focus on customers, brands and products, he said, as he prepares to replace Herbert Diess at the helm of Europe’s largest carmaker, marking the end of an era. Diess is stepping down as chairman of the board of management of the Volkswagen Group, effective September 1, the company said in an unexpected announcement on Friday evening following a supervisory board meeting. The decision was made “by mutual agreement,” according to the statement. Blume, currently boss of Porsche, will continue in his role leading Porsche in addition to h…