Thanks TD.
I had not even considered the differences in architecture due loss of bleeds, and pneumatics playing such an enhanced role. "In the gearbox" does not actually involve the drive system. "Reduced service life" does have a haunting familiarity, however. It communicates a foresight that I believe was ignored in the -900.
It also does not address what might happen if a problem appears on wing. Anything that shortens a service life, unaddressed, might shorten, well, other types of life.
Tentative hat tip in the direction of Derby, then?