Southwest Airlines has revamped its schedule through Aug. 5 to account for not having its 34 Boeing 737 MAXs as the model’s grounding continues to keep operators shuffling their schedules and fleet plans.

“While the timing for the return to service of the MAX remains unclear, what is very clear is our commitment to operate a reliable schedule and provide the famous customer service you expect from us,” Southwest president Tom Nealon said in an update shared by the airline. “Our revised summer schedule allows us to accomplish those objectives.”

The Dallas-based carrier operates more MAXs than any other airline, and flew about 200 daily departures with them before FAA issued an operational ban March 13, joining the rest of the world in taking action following the March 10 crash of an Ethiopian Airlines MAX 8.

Chicago-based United Airlines, which operated about 40 daily flights with its 12 MAX 9s, has been canceling with shorter notice. The airline was forced to delay the May bidding process for pilots when it canceled “a number of 737 trips” on April 4, just as the pilots were supposed to start bidding on May schedules. The United pilots’ system schedule committee said it asked airline “on multiple occasions if a contingency plan was in effect to ensure this type of last-minute fire drill could be avoided, but we were rebuffed,” the committee told pilots in a recent message.

American Airlines, which operates 24 MAXs, on April 7 said it would extend its MAX-less fleet schedule through June 5. Dallas/Fort Worth-based American said it would cancel about 90 flights per day as a result.

Schedule changes, cancellations and crew-scheduling disruptions are the most common ramifications of the global grounding of all 376 MAXs in service, but some airlines are taking more aggressive steps.

Canadian LCC WestJet extended one lease on a 737NG, and is delaying the start of a cabin-modification project for its 737NG fleet until at least August, and possibly longer, if the MAX fleet remains grounded. Some of its 13 MAXs are slated for the cabin changes as well, and the airline moved the MAXs to the front of the mod line, which was slated to get started just as the groundings went into effect.

Sean Broderick, sean.broderick@aviationweek.com