i don't know how long or even why this downtrend is lasting but if you really think the downtrend is going to last until March then the obvious choice is to cut your losses NOW before the bottom is reached and you are left with nearly nothing!
I would not count that as a good advice. Anything that did not make you to buy at the top, or probably cut loss when maybe at 5% to buy back lower when the market started a deep correction, then there is no point selling after a pretty huge percentage.
Better still, you can hold on until it reaches that bottom and there is a chance of recovery in the market and buy more with fiat at that point; you will be so surprise the profit you will make in this situation.