Question, tell me please if there will be bitcoin split for example is the difficulty of the mining should be changed?
part of difficulty is based on how much hashrate is mining bitcoin or in other words how many miners.
if it splits and the splitted chain (BCC in this case) will obviously won't have enough miners on it.
the difficulty will stay the same at first but after reaching the difficulty adjustment block (which is every 2016 block) it will be readjusted) and comes down.
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BCC's difficulty will be adjusted quicker:
Forking rule:
REQ-7 Difficulty adjustement in case of hashrate drop
In case the MTP of the tip of the chain is 12h or more after the MTP 6 block before the tip, the proof of work target is increased by a quarter, or 25%, which corresponds to a difficulty reduction of 20% .
RATIONALE: The hashrate supporting the chain is dependent on market price and hard to predict. In order to make sure the chain remains viable no matter what difficulty needs to adjust down in case of abrupt hashrate drop.