When the system broke, it was all hands on deck (and
it was illuminating to see how crowded the aisle could be when everybody was called into the room from out the back - not sure what would have happened had the failure occurred in the late evening/middle of the night.....)
Some ALMs were more help than others - much like the more experienced ATC's were more help to their colleages than the new guys (generally speaking).
An off-the-record conversation confirmed what I suspected: it has been some time since the one-centre-offline-contingency plan has been updated.
And some people still reckon there are good reasons (mostly saving money) for just having one single ATC centre in Australia. Unbelievable.