New ATH
BTC is climbing a bull channel which will reach $3,000 just as it intersects with the deadline for the fork. In reality, it will probably get there a few hours early in anticipation, likely followed by a very quick dump and a burst of buying that will take it to nearly $3,300. (Totally guessing here because who tf knows?)
Inverse Movement
Usually BTC and the rest of the market move together. However, when BTC was on a major tear recently, people cashed out alts to ride the Bitcoin wave. (This has happened before, even without the promise of bitCoinCash.) And if/when Bitcoin dumps, people may cash out BTC in favor of alts. We may see BTC once again move in the opposite direction of the market, only this time it will go down while the rest go up.
BTC will be worth more in the future than it is today, so if you're a holder, just keep on holdin' and sleep well.