Southwest Airlines is also continuing to make cancellations.
The changes are meant to decrease the chances of triggering the Maneuvering Characteristics Augmentation System, or MCAS, which is believed to have played a role in the Lion Air crash in October.
Garuda has only one 737 MAX and had been reconsidering its order before the Ethiopian crash, as has fellow Indonesian carrier Lion Air, which experienced a deadly crash in October.
The airline will however delay the April delivery of another MAX jet until the cause of the crash is known, Qatar Chief Executive Akbar al-Baker.
In the simulations with the current MCAS software, the test pilots used existing procedures to disable the system, while test flights using the new software required less intervention from the pilots, the person said.
At the gathering, pilots from the three American carriers, plus two smaller non-US airlines, ran simulated flights created to mimic the situation that brought down the Lion Air flight in Indonesia previous year, using the current and updated software, according to the person briefed on the session.
Kenya Airways (KQ) has the option of buying more of the older 737-800 version of the Boeing aircraft that does not feature the suspect software, but this could see it lose the fuel efficiency associated with the new jet. The incident was the second major crash involving the aircraft in five months.
The company has issued more than 200 invitations for what it is billing an "informational session" at its base in Renton, near Seattle, on Wednesday.
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The Verge says the beta performs "well" on Windows 10, and that it comes with a few custom changes to the user interface, as well. But the most important thing is that Microsoft Edge can finally be considered an alternative to Google Chrome altogether.
The Federal Aviation Administration expects Boeing's update this week.
Airlines and aviation oversight bodies around the world grounded the 737 MAX planes earlier this month after the crash an Ethiopian Airlines flight.
The airline had been flying 24 of the Boeing planes, and said it is canceling the flights in an effort to provide more certainty, and avoid last-minute scheduling changes. After the update, the system will rely on data from more than one sensor before it automatically pushes the plane's nose lower.
The New York Times reported last week that the pilot of the doomed flight had not trained on a 737 MAX 8 simulator.
Boeing has not said what it expects to pay to relatives of the people who died in the Lion Air and Ethiopian Airlines crashes.
Ethiopian Airlines did not respond immedidately to a request for comment about the meeting.
The manufacturer is fighting to keep its flagship MAX project alive after Indonesia's national airline, Garuda Indonesia, cancelled orders for the jet worth billions of dollars last week.