This whole situation worries me a bit as well. I usually hold my coins on a wallet, because it's safer, than leaving them on a exchange, where you normally don't have control over your private keys. But because of the lack of replay protection on this fork, I just don't know what to do. I know exchanges and wallets are going to implement their own replay protection, so it should be ok to leave the coins on a exchange that does that. Right now it could even be safer to hold them there, if your wallet is not implementing their own replay protection.
I'm using Electrum right now, and I need to do some research, to see if they will do the same. If they don't take any measures, and since I don't really want to lose any of the coins (BTC to hold, and B2x to dump), I guess I wont be moving any of my coins around, until all the dust settles.
Yeah I had been moving my coins to electrum for the forks, though the Bitcoin Gold fork happened two days earlier than they said it was going to so I ended up not doing it soon enough for that fork. But then I was looking up how to get B2X coins from electrum and I couldn't find electrum saying they would do it and i found some long process on the internet for splitting your own coins and it just seemed like such a hassle when coinbase said they will do it for you within a day after the fork. So I'm just gonna store my coins there until they are safe to move. Then I'll sell B2X for more BTC and move BTC to electrum or cold storage.