Trent upgrades

It is always a guess for us. It is difficult to get hard data. The best data would be from the test flights of the Trent XWB on MSN001 where you have both engines on the same frame, so Airbus should have the real numbers.

Even after the upgrade a Trent XWB will IMO burn less fuel then a Trent 900 EP2 version.
The Trent XWB is thought to have 15% less fuel burn against the original Trent 700. (before EP and EP2)
The 900 is somewhere in the middle between them and the two upgrades, EP and EP2 makes it a moving target.

The disadvantage for the XWB is that it is heavier than a 900.
There would be the cost of certifying the new engine on the A380.
Apart from the technical aspects there are also agreements between companies around the engines for the A380.
Perhaps someone has to be bought out.

I do not expect a re engine of the A380, but rather further improvements of the Trent 900.