$BTC is sinking today as we lead into the futures opening.....likely setting the tone for what is to follow tomorrow.
I suspect the uncertainty behind $AAPL is what's driving this.
The 69k level rejected hard and pulled back, the 50 and 200 Day MA offered very little in terms of support and the price action is cutting through the support levels now, so far at the lower support level at the 0.78 Fib at $57k.
Below the 0.618 Fib for a pull back means weakness and if the 0.88 Fib is lost at $55k, then the broadening channel trend line becomes a possibility.
But I suspect the larger amber 0.38 Fib at $51k will play a part first.