I guess an insider can confirm this but my understanding is that with the closure of the engine centre - components are sent overseas in I guess what might be termed sub assemblies - they join the queue to get serviced/overhauled by the manufacturer - and the next set of sub assemblies on the line which have already been overhauled get sent back to be installed.
So instead of all the work being done in Australia - it is merely pre assembled components serviced by the manufacturer which gets re assembled in Australia.
Yet again happy to be corrected - but the returned components may not be Qantas's original parts - but may have been in someone else's engine for a while. So then the reliance is on that particular operator to have a detailed working history of the engine.
In the end Qantas loses true control of the engine components - it only has a partial history (and possibly not entirely true) of the engine components - the end result is a very poor and sad state of affairs.
.....but on the bright side the spin doctors get to say they are still maintained in Australia......
Where once RR would come to QF to find out about their engines, now QF can hardly keep them on the wing without them going bang.