Quote from Ebo:
You need to Register as a "marked to Market Trader" by April 15th of the year prior to achieve MTM status anyway. So you are an individual until next 4/15 anyway.
You can still deduct expenses as an individual, they are just subject to 2% exemption, just take more!
Quote from DisciplinedHedg:
Just because you have not or chose not to elect MtM has nothing to do with whether you choose Trader in Securities as your occupation.
So even though the 4/15 deadline has passed, you can still be a "Trader in Securities" and deduct expenses as a trader without the 2% limit. Your accounting method just won't be Mark to Market for this year.