You can simply check or verify this by actually looking at rainbet signature thread and see that some members changed their addresses. Maybe you can see how I got the information
What I am seeing is some people requested their address to be changed but no one mentioned anything about suspension of kucoin exchange or address poisoning that is why it is really confusing why you came into such conclusion?
I don’t see the reason why they need to mention that in the thread that they want to change the address. It is such a coincidence that what the OP is saying is actually right about KuCoin suspending their accounts and users changing their wallet addresses on the same campaign.
We rarely see campaign participants of the same campaign in numbers changing address all at the same time, so OP is actually right and the need for them to stop receiving payment in that address henceforth to avoid not having access to their money. If they follow up the case, the accounts will be free from suspension.
But it is still better to stay off centralized platforms because you can’t tell when they’ll come at you again after receiving another money, they could just ban your account and never release the funds to you.