Do you think these rumors are real? I tend to think yes and I think this will happen soon.
To be well understood, I believe in Ethereum's potential (even though so far I have lost money investing in Ethereum, but I notice that it is still a good project and this will makes it to explode one day) and I still believe that by the end of 2018 it will have an increase of thousands of dollars, but at the same time I feel that it will drop much more than it is now before starting the growth again.
What is the basis for your opinion that Ethrerum will fall to 400? I do not think that the second most important crypto currency and the basis for most coins can fall so in value. This is possible only against the background of strong negative news and the fall of the whole market.