I was speaking with Pete Bissonette a couple of days ago, when he mentioned to that LSC was going to completely revamp their line of paraliminal products. He hinted that there would likely be a big sale very soon, where they are hoping to clear out their inventory in preparation for some big new paraliminal projects and I think CD versions was a part of that.
It sounded like they may be out of stock of many of these titles fairly soon (after the sale) and that there might be some time when there wouldn't be any available as the new ones were in production.