The most likely execution order is the one which leaves you with the greatest possible loss. Unless you are the one orchestrating events.  ^^

This also means that the most profitable action is to either use another exchange or wait until the spasms end and regroup at whatever level that is. The panic-sells always bounce at a much lower level than they stabilize at. (This deep bounce is induced by people who sell blindly during the fall, which is practically everyone except the orchestrator.)