Why China shut down mining farm? Carbon Emission.
here is one great article, Predicted this shutting down action.

Bitcoin Segwit2M （B2X)-Green and Scaled bitcoin.
https://bitcoinnewyork.medium.com/bitcoin-segwit2m-b2x-green-and-scaled-bitcoin-3f0b0b32ac64

China are shutting down all high energy consumption, high pollution factory, because of Carbo emission. this is global govs unified action.
we will see the hashrate drop 30-50% at the end of this year. because in winter, all Chinese farm are shut down : no enough hydro , and gov control the carbon emission, shut down the coal-burn electricity supply.

good timing for over sea miners join mining. if you have cheap than 4 usd cent electricity, and enough capacity.