Now BCH block tiime is 1m 30sec = 1.5min
There is 400 blocks left for retarget, it is approx. 600 minutes or 10 hours+-.
So it will affect on BCH mining profitability, because of block time, and it also can affect on BTC network hashrate (block time 14min now)in a short period of time.
Prepeare for dump/pump... I think time deviation from the event +- 4 hours...