I'm afraid Naxos don't seem to be bothered with completing cycles these days and keep churning out far too much 10th rate music by complete non-entities in their American music series.
I strongly suspect that these are projects that are being financed by the composers or foundations and the like. To some extent, Naxos seems to be turning into a "vanity press" of sorts. Please correct me if I'm wrong, but I really can't believe that Klaus Heymann is willing to foot the bill to promote some of these obscurities!