It was cost cutting regarding the language speakers on the PERTH TOKYO Flight.
Perth Longhaul have been flying the Tokyo trips for the best part of 3-4 years now. In nearly all cases 2 or 3 Japanese speakers are planned as crew - this obviously helps customer service and in the event of an emergency helps significantly. An incident on a Melbourne Tokyo QANTAS flight highlighted this (there were no language speakers on board when the aircaft had to divert) , and as a result the Japanese language speakers were returned to these services.
In the last bid periods out of Perth, this bid period inclusive and particularly the Tokyo Perth Flight that this incident has just occured on, the flights have been crewed by Short Haul Perth based cabin crew -they are much cheaper to use on long flights with large transits (ie 80 hours). This change is a direct result of cost cutting (and their FAAA. In so doing there are no Japanese language speakers on board as part of the normal crew compliment. In all of QANTAS's wisdom, after the short haul crew on these services started serving Japanese meals for dinner instead of breakfast along with a few other stuff ups, they realised that yet again they needed language speakers on board. So QANTAS's short term money saving solution has been to have a short haul crew complimented by 1 long haul crew language speaker (instead of the minimum 2 normally used). This 1 extra crew member is purely for PAs etc and are treated as a "Sherpa".
In this particular incident, the Sherpa had gone sick in Japan.
The only language speaker on board was an off duty Long haul Perth based Japanese cabin crew who was paxing home from his family in Japan.