Fairly certain it is discontinued, but it can still be found NIB. Purchased a satin 440c a couple months ago new on a well known auction site at a very reasonable price. Have not used it much yet, but really like the size.
I have a 440c cub and it is a GREAT knife! easy to sharpen, and I'm not afraid to hurt it. The sheath TOTALLY sucked (mine was the kydex one, not the newer thermoplastic spider-man looking one), so I took it apart and re-designed it... MUCH to success! All it took was a hair dryer, towels to hold the new molded shape while cooling, a drill, and the use of MAJOR calluses (sp?). nice knife...
I'm guessing that it's just the usual turnover. Knuts are always looking for something new. (Non-knuts just go buy something cheap and get on with life.) Companies that deliver the new stuff make money. Companies exist to make money. If all you really need is a tool to cut something, there are plenty of choices.
I'm guessing that when sales drop to a certain point, or don't pass a certain point in a reasonable amount of time, the model gets axed. Those that survive will be the popular ones. Darwinism in the market.
That said, I unloaded my Cub because the handle wasn't to my taste. It was much smaller diameter than I like, and I have smallish hands. For a small utility type knife, I thought that it had an awfully thick blade. The sheath sucked. If I had a brain I would just go buy a Mora or three and be done with it