They have got that data already.
The big main bearings are through flows. The only grease filled bearings are down in the power take off...the gearbox that drives ancillaries. They are cool and away from combustion heat.
In my view they have taken this particular design to the limit. They want to hit all the new targets with the stuff they have now. Thats impossible.
I think there is only one additive that may be able to help the oil people and it is called "graphene". Then again that is carbon and they already have a coking issue so I am guessing.
This is a good site and tells us how propulsion is going in the future. I just hope they choose the right gang of subcontractores when it comes to bearings
GE Aviation entering new propulsion era with multiple R&D programs
Regards