"The longer we stick around the more likely we'll get our arses handed to us. Still, with great stupidity comes great reward.
I guess more than 20 Arbitration Disruption waves are possible if you are not doing it solo (the rest of the team apparently was not willing to take the risk). The risk to die when dealing with lvl ~350 enemies is just too big when there is nobody else around.
On survival I would go further than that since you don't have to care about certain tasks other than killing NPCs and you are not locked in animations when picking up or activating stuff (which is highly dangerous).