BCH sudden rise... Why?
Currently, the increase in Bitcoin Cash price has resulted in mining BCH becoming more profitable than mining BTC.
It has also generated substantial interest and is driving trading volumes.
The uncertainty around SegWit2x and the prospect of another fork on BTC has also resulted in some people shifting to BCH. Transaction volumes have increased in BCH, with a single block clearing over 37,000 transactions.
Currently, BCH has played the role of an altcoin killer and has not cannibalized the value of BTC. If the scaling prospects of BTC get stalled again, then a lot more people could shift to BCH from Bitcoin.