No exact time has been chosen yet, we're in build+test phase right now. But I believe it will be soon...
However, I am going to recommend to exchanges to wait maybe a week, to reopen. So that the patch can be properly vetted. I think it's best not to rush things right now, and instead err on the side of caution.
Perhaps more conservative.. but we've got to stop shooting from the hip here. I did this with my spare time, and I'm no uber developer either. So please let's take some time to stress test this patch, this time.
Is there any way to make sure that no exchange can reopen to early? If it is voluntary, i don't think that they'll wait one week...