As far as I know, the attack is over. However, Bittrex (and perhaps some other exhances also) is holding back tons of BTG coins, because they wallet is "automated maintenance" since Saturday. (However, the trade is on.) What kind of manipulation is this? And they are unable to recover those coins, which are stuck.
Bittrex's BTG wallet is still offline. Now the official reason is: "Wallet Offline - Awaiting feedback from developers" Dear developers! Do you know anything?
Bittrex's BTG wallet is still offline, and they have no willingness to solve it, they are simply forcibly closing related support tickets without any meaningful work.