The chart is forming a triangle. I brought here the same 4 hour chart that you used. If it doesn't continue sideways and breaks the triangle line on top, that will be a signal for upward move. If it will stay above 16 000 by the end of this year, that will be even stronger signal. As for previous crucial points, staying above 16800 by 2 or 3 candles (8-12 hours) is also a good signal to buy.
Depending when, but of course breaking 17.5K point is a strong buy signal.