We spent tons of time getting all set up back when we did it in Wrath. The night before we went to do it our fury warrior got hacked. Thankfully they restored his gear and we were a go for the next day.
I kid you not, less than one minute after we got Herald he went offline. Before loot had even been handed out he got re-hacked. We like to think good guy hacker waited for us to finish Herald first. :3