Following the footsteps of Southwest and American Airlines, United Airlines on Friday delayed the return date of Boeing’s 737 MAX aircraft to service towards early March 2020.

On Friday, the company said “it is pulling the 737 MAX jets off its schedule until March 04 of the next year,” two months later than a previous estimate, implying the cancellation of thousands of scheduled flights.

The top-selling Boeing jets have been grounded since March 2019, following the two deadly crashes. In the second crash, 346 people were left dead.

After the two major incidents, Boeing has faced criticism and trouble to win global regulators’ approval for proposed fixes to the aircraft and get the planes flying again.

In a statement, United said it was working to minimize disruptions for the flying public, rescheduling flights or making other offers.

“We have cooperated fully with the FAA’s independent review of the MAX aircraft, and we won’t put our customers and employees on that plane until regulators make their own independent assessment that it is safe to do so,” it said.

Boeing says it is hopeful in getting regulatory approval for a return to service before the end of this year but the giant manufacturer has delayed its estimate for the resumption of commercial flights until January, to allow for changes to pilot training.

(With input from agencies)