Pretty sure it doesn't matter. It's just the ticker. You can still buy and sell through CS you just have to do it with a broker and they waive the broker fee. They just charge the 6.99 or whatever.
It's real simple to find out. Jjust go online and attempt to do a buy or sell online and go to review order. It zero's out everything for me although for som, it doesn't
Merrill Esdge will not allow you to buy or sell otc online or with a broker.
So far it appears that only eTrade has no restrictions