"AOA DISAGREE alert not in original MAX design"
Quite extraordinary IMO:
FAA on page 26 of the Final Rule/AD: "The AOA DISAGREE alert is a standard design feature on the 737 NG fleet (600/700/800/900/900ER) and was intended to be standard for the 737 MAX, but it was instead erroneously linked by the manufacturer to an optional AOA indicator (which some refer to as a gauge). The optional AOA indicator is a round dial that provides graphic and numeric AOA position information on both PFDs. Because of this error, only airplanes with the (optional) AOA indicator had a functioning AOA DISAGREE alert. This was incorrectly implemented by the manufacturer during the display software development, and was not identified until after the 737 MAX entered into service."