According to my Boeing manual:
During an approach with two or three autopilots engaged and below 330 feet RA an increment of nose up trim is automatically applied for flare. If the autopilots are subsequently disengaged in the approach, a forward control column force of 20-30 pounds may be required to counter the automatic trim condition. If an automatic multi-autopilot go-around is performed, the increment of automatic trim is removed.
Anyway, we're splitting hairs. This wasn't the cause of the incident so it's not really relevant.
