I think I have misunderstood the issue. I updated my Navigraph-carenado files to the latest cycle, 1601, inserted the lines above into my dll.xml-file and had the navigraph updater updating it. But the G1000 screens still show "maps effective until 26th of march 2016, so now I understand the trouble. Mind you, I don't have the Navigraph addon from Carenado, as I update the cycles directly from Navigraphs site.