safetypee
If so, then the basis of the certification is flawed.
I don't see why. The preliminary report says
"At 05:43:11, about 32 seconds before the end of the recording, at approximately 13,4002 ft, two momentary manual electric trim inputs are recorded in the ANU direction. The stabilizer moved in the ANU direction from 2.1 units to 2.3 units."
The crew could still wind the stab trim ANU using the manual electric trim 32 seconds before impact. The question has to be why didn't they use the manual electric trim to remove the elevator load completely then isolate the system using the two pedestal switches.