The TCB has been out-of-stock at Hobby King now for several months. After emails too numerous to count, I finally reached a real human being yesterday who informed me that this is not a temporary state of affairs, but rather that Hobby King has decided to discontinue production due to insufficient sales.
In the roughly one year that the TCB was available HK sold approximately 500 units. That's not much by HK standards but for a one-man open source project, selling into one of the smallest market segments of the entire RC industry, it seems to me like a respectable success and really it's a lot farther than I thought this would make it in the beginning.
I am not certain where the project will go from here. The sound card development was finally brought to a mature stage late last year, but although it can operate as a standalone device with common RC equipment, I'm not sure it makes sense to pursue it further without the TCB to accompany it. Manufacturing has always been the weak point of this endeavor. It's unclear to me if that can be overcome again, but if something transpires I will certainly announce it here as well as in the
Project Status thread over on the Open Panzer forums.
In the meantime I will of course continue to support those who already purchased TCBs, and as always all schematics, source files and firmware remain completely open source for what it's worth.