United is the latest airline to push the Boeing 737 Max's return back, despite Boeing's increasing confidence about the plane's recertification

United Airlines said on Friday that it was extending the cancellation of 737 Max flights until at least the first week of March, 2020, matching American and Southwest Airlines’ timeframes.

Boeing suggested this week that the plane is moving closer to recertification, and that deliveries of new jets may resume in December, but US airlines have become increasingly sceptical of Boeing’s stated time frames. The plane maker said in July that it expected the plane to return to service during the fourth quarter of 2019; it recently said that January 2020 was more likely.

Under United’s new timeframe, the Max will be pulled from the airline’s operating schedule until at least March 4, 2020. The airline had previously removed the plane through January 6.

The airline said that it expected to cancel 93 flights per day in November – 2,800 for the month, 75 daily flights in December, and 56 per day January through March 4.

American had last stated that it planned to begin reintroducing the jet to service on January 16, assuming that Boeing would meet its expected timeline of winning US approval during the fourth quarter of this year. American now plans to cancel flights through March 5, while Southwest pulled the plane type through March 6.

Last week, regulators found gaps and substandard documents in the recertification paperwork submitted by Boeing, and asked for revisions. Reuters reported that Boeing confirmed it must resubmit revised documentation.

The 737 Max, the latest generation of Boeing’s best-selling plane, has been grounded since March after crashes in Indonesia and Ethiopia killed 346 people.

Do you work for Boeing, or one of the airlines affected by the Boeing 737 Max grounding? Contact this reporter at [email protected].

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