Just want to correct what is almost certainly an error in the comments:
I very much doubt that RR still owns the engines in a legal sense. RR almost certainly "owns" the engine failure in a technical and financial sense (maintained on a power-by-the-hour contract, and also almost certainly a warranty failure). QF owns the engine in a legal sense and "owns" the failure as far as pax are concerned (there may be an impact on loads/yields, and is already an impact on costs to get out from under the operational disruption).
And now onto opinion: things have changed in the engine business in the past few decades. Setting up an engine overhaul shop is vastly more complex than previously (especially for such a big donk as this), at present I suspect there is only one engine shop that actually has overhaul capability (Derby...). Airlines want to reduce risks, especially on big-ticket items such as engines, so many new engines (and almost all of these engines) are sold bundled with PBH contracts, so the (overhaul) maintenance is already decided "at birth". This makes sense for RR, because they get the overhaul revenue for ever (and of course that is way more than they make from selling engines) and also reduces their reputational risk (they've also got a pretty good monitoring centre so they can usually keep on top of developing problems).
For an airline, it makes little financial sense to set up a new engine overhaul capability. You'd need $X million (and X is *very* large), without the same knowledge that a manufacturer has of the design/weak points etc. It doesn't make sense for a small engine fleet (X divided by the fleet size is frightening), and if you tried to make a business out of it by taking in other airline's engines, you're up against the manufacturer who tied up the overhauls at birth on PBH contracts.
Mind you, there maybe a business in being RR's captive south-pacific overhaul shop, but I'm not sure you could get RR's attention right now to arrange it... and of course you have to be cost-competitive (with RR taking a margin on top) to be in the game. Not sure the Trent 900 fleet is going to be large enough to need a south-pacific shop.
btw, third point, most people don't know that most modern electronics almost never gets turned off, even when the power switch is used. They keep the time/date correct, don't they? Typically they go into a lower-power state whereby they get put to sleep and woken up by a timer a few hundred times a second just to see if anything is happening (like the power switch being pushed). Some gadgets don't even turn completely off if you remove the battery (because they've got another, small, built-in battery to keep the clock running).
But of course, the "off" state is vastly lower-power than the "on" state, and therefore safer. And of course, we should turn the things off when required, as under certain (fault) conditions there is a possibility of compromising avionics. I do wish that posters here would stop throwing stones about this, though, as I think there's many experienced pilots who have forgotten to turn off their mobile on a sector...