I could be wrong, but I thought Ameritrade was saying that the last day you can call them to write off non-marketable securites, was on the 22nd. I'm about 99% sure that's what they were saying!
Yes, I just signed on and here's a copy/paste of what they said:
Non-Marketable Securities
Please note the last day to request the removal of a non-marketable security from your account before year end will be Friday, December 22 at 4 p.m. ET. Any requests submitted after that will be processed on a best-efforts basis.