Is crypto winter really over?

BTC/USD Bitfinex pricing chart from Jan 2014 to Jan 2017

We certainly are experiencing a thaw, with evidence of spring around us. But will it last? Will crypto winter turn out to mirror the “real” 2018–2019 winter in the northern hemisphere? In other words, is this going to be a lasting spring?
The honest answer is that based on the chart evidence alone, we cannot know.
We have now seen a revival in bitcoin prices of almost 80% — not quite 2x. Other coins have doubled, tripled or even quadrupled in value. Bitcoin experienced a one day price rise of about 25%. If we look only at bitcoin, then this does indeed hint at a recovery. A sustained price increase of 80% is historically significant. By comparison: During the last bear market, the final false recovery took place in the early summer of 2014, when prices recovered by over 40% from the low 400’s to around $650. The next significant upswing did not take place until mid 2016 — two years later, a fact which should caution us against overestimating the significance of this (fairly early) strong recovery.
If the time element prevails, then we should expect a resumption of sideways lackluster trading: While it’s true that during the previous recovery the low was reached after approximately one year, two more years were needed for prices to regain the highs of December 2013. And though the bottom was reached after a year, the “bottoming out” period lasted for about 9 months — far more time than we spent lurking around the bottom thus far this time. If historical patterns are any guide, 5 more months of dawdling would be par for the course. In 2015 prices went sideways for 9 months. 
Again, looking at historical patterns, what follow-on movements would confirm that we are looking at the beginnings of a new bull market? In the period Jan 2015-Jan 2016, the btc price took almost a year to double from the low around $200 to $400. If we are looking for confirmation of a new bull market, a similar doubling would certainly be helpful. To accomplish that we would need to see a spike up to around $6200. 
So would a level of $6200 be enough to confirm a new bull market? I think not. Certainty is never on offer. Patterns rarely repeat exactly.

Some helpful links: