According to T.Demark rule, when a trendline is broken and we see a daily close below it we calculate the gap between the highest candles high to that trendline and subtract it from the closing price of the candle that breaks the trendline. Also we can see that the -1.618 fibonacci level of the last rally is a very close number to that. So I will look forward to buy after this target is reached.
The only thing I will consider is how big of a support will BTC get from this trendline during the fall. I don't expect this trendline to be broken at first try. It is likely to see a %38-50 retracement of the fall from 8506 dollars from this trendline. If we see a higher low formation or if we break the %50 retracement level then I will consider closing my position and look forward to buy.