Sadly the widebody operation is still a victim of being too small a fleet, together with the maintenance being carried out by a contractor (in this case, QF Engineering) who further contracts out maintenance in some ports.
And I'm not making a judgement call here - it's just that whenever an airline is in that kind of situation, they lose an element of control of the operation. Evidence the narrowbody operation; not nearly as many 'big' disruptions - part of the reason being that it's an entirely 'in-house' operation. And it helps that there are nearly 40 airframes to fall back on.
By year's end, disruptions may well be more easily handled - more and newer units into the fleet. Quite a few...
It's a situation that V don't have to worry about for the moment - nice shiny new jets don't fail all that often. But maybe in a couple years time? Who knows.