I have been a loyal customer of Southwest Airlines for many years--so much so that I flew enough miles last year to earn a companion pass.

However, ever since the Boeing 737 Max aircraft was grounded by the FAA on March 13, 2019, Southwest Airlines--along with American and United, which also have grounded 737 Max aircraft in their fleets--have been scrambling to rework their schedules around the missing aircraft.

Now there's even more bad news for Southwest flyers. Yesterday, Southwest Airlilnes announced that it was pushing its scheduled return of the 737 Max aircraft to June 6, 2020.

This action will result in the cancellation of approximately 330 weekday flights during the period from mid-April to early-June 2020. United and American Airlines had previously announced that they were pushing the return of the 737 Max to June 2020.

Unfortunately, the flight schedules of a "limited number" of Southwest customers who had already booked travel will be affected by this shuffle. These customers will be "re-accommodated" by the airline.

According to yesterday's announcement:

We previously removed the MAX through April 13, 2020 to offer reliability to our operation and stability for our Customers. Based on continued uncertainty around the timing of MAX return to service, as well as Boeing's recommendation for Pilot simulator training, the Company is proactively removing the MAX from its flight schedule through June 6, 2020.

The case of Southwest Airlines is unique because, to keep costs down, it relies solely on one kind of aircraft: the Boeing 737. The airline currently has 34 grounded 737 Max aircraft--more than American (with 24) and United (with 14). In addition, the company had orders for 200 more 737 Max aircraft when the planes were grounded by the FAA last year. Those orders are on hold until further notice.

For its part, the FAA is taking a wait-and-see attitude to testing and approving Boeing's eventual fixes. Said Lynn Lunsford, spokesperson for the FAA:

The FAA is following a thorough process, not a prescribed timeline, for returning the Boeing 737 Max to passenger service. The FAA will lift the aircraft's prohibition order when we deem it is safe to do so.

Southwest remains confident that the 737 Max aircraft will eventually return to service, and that it will do so safely. According to the company's announcement yesterday:

Southwest Airlines continues to monitor information from Boeing and the Federal Aviation Administration (FAA) on the impending 737 MAX software enhancements and training requirements. We remain confident that, once certified by the FAA, the enhancements will support the safe operation of the MAX.

As a big fan of Southwest Airlines, I certainly hope this is the case.