Hii , I'm afraid if Bitcoin back below 6K again, should I hold till 20K or close right now?
You should not be so worried about the future of bitcoin because the answer will be a bright future. The price of bitcoin is recovering very well and once again holding strategy is still the best.
I think you should hold it until its price is $ 30k at the end of 2018. Even though it's a long time but that's the nature of the job. You need to be patient, delicate in making investment strategies.