A more detailed log-scale chart also points to the same conclusion that the peak before any 27 month crypto winter would be at least $40k $50k, with a possibility for $100+k:
https://www.tradingview.com/chart/BTCUSD/BzKoYDVE-BTC-Let-the-shorting-Begin/That chart also alerts me to another possibility, which is a several months correction from the current level or $40k $50k level, and then the final blowoff peak at $40k $50k or $100+k respectively. IOW, the start of the long crypto winter could be delayed into 2019 or 2020.
In any case, I think it is best to HODL now. I doubt the current level is the start of a 27 month crypto winter.
P.S. given the potential gain for BTC from the current level is ~3X (or maybe 5X at an extreme to $100+k), the altcoins are likely to moon soon and gain on BTC, because most of them have 10+ X gains potential before the next crypto winter.
Crypto winter if it ever comes could be due to any one of the following reasons:
The 3rd one has the highest probability
after we hit the $40k peak. But the bottom would be > $10k.
The last (4th) one [the Tether/Bitfinex collapse] may occur during the 3rd one, and may also include: