Omwith has to do with the possibility of a BTC-split, if this happens you're never sure which BTC you get(from exchanges) and if you get the BTU, best to read some on Internet, some exchanges stand behind BTC segwit etc but not Roger Ver, also some exchanges will halt trading on august 1 and some withdraw fees have shot up.
Most advise you to put it on a wallet with private keys, Bitcoincore, Electrum and wait it out (go in Alts, like Steemit, but i can't advice there.). Perhaps good trades can be made?! Also when you withdraw best some time before 1 august, to be safe.
Just Google BTC segwit 1 aug etc