787 Shafts and corrective action
Seems to me that given the shafts have individual manufacturing records, and that suspect -1B shafts (or shaft lots) have likely been identified and segregated, that NOT ALL shafts (FMS) are replaced before delivery.
That said, we are reminded that the customer is king, and pressure from the customer could upset this plan and force 100% replacement, even if technically unwarranted.