No, they just are sucking. Volume 6 was released in February, but when I went to order a month later, it was sold out, everywhere it seems. Vollume 7 is still planned I think.
Actually, looking through a few things, it seems that volume 6 was never actually released, ADV held it back when anime shit was dropped earlier this year. Supposedly, they still plan on releasing 6 and 7 at some point.