A shift is happening by the end of this week with Altcoins. Looking at the Daily charts for Ether and XRP, there is a monster triangle pattern created by the long-term ascending support and the descending resistance that started from mid-January 2018. With both coins, these trendlines will meet around the coming weekend (18-20 March 2018).
Ether-Euro Daily Chart
XRP-Euro Daily Chart
Source: Charts from TradingView with Kraken data
If I were to make a prediction, these two altcoins will initiate a bullish move later this week as the support seems to be long-term and quite strong. However if we see the price falling below support, I think we may see a significant sell-off. I quickly checked if this pattern also exists with BTC, however it is not as obvious as the #2 and #3 cryptocurrencies. THis is why I think this might be mostly limited to altcoins.
Note: I am an amateur trader and I am performing this exercise for my own research and analysis. This is by no means a form of financial advice and should be treated as a blog post for entertainment purposes. It is also based on historical data which may not be an indication of future price.