Most of these problems are not exclusive to HNSS, the Zecco/Penson issues starting cropping up in June, those who realized the winds of change moved their accounts over the Fidelity, who, still accepted pretty much all securities. They must have had too many moving sub .75 OTC stocks over and, decided to cut it off. TDA has put random restrictions on for as long as I've played OTC stocks, however, there's no doubt that recently they really stepped those up.
They're probably doing the normal panic sellers a favor down here though not allowing them to sell. However, it really sucks not having the ability to buy or sell a security, especially if you already own it. It's not right.
So, the issues are not just with HNSS, going on all over OTC land. Stocks still seem to be trading fine, even with them. Traders/investors, have to adapt or die unfortunately. Many are adapting.