At first I just assumed it was back-ordered like most of the things in the shop. Now, it's the only remaining sold out item; even the roof rack is in stock regularly.
I guess they must be planning on another production run sometime in the future, otherwise they would remove it from the page, right? At first I wanted one of those HPWCs with the Nema 14-50 plug on the end, but they just completely discontinued those and removed the page from the shop.