I'm curious to know what happens in these TRA sectors - do the all the conflict alarms get turned off, screens switch off etc? I'd be surprised if there is no-one looking at them - but just not enough (qualified) people to provide the service. The airport that most recently started all of this - Darwin - clearly had some staff on duty through the nights - just not enough.
So for this incident, I wonder if it is possible someone noticed the impending problem - or an alarm went off - and that caused the instruction to go out - even though they weren't technically controlling the airspace?