Both American Airlines and Southwest Airlines have extended their cancellations of flights on the Boeing 737 Max plane through March 2020, according to Reuters. American previously canceled 140 flights a day scheduled on the 737 Max plane through Jan. 15, 2020, but has since extended the grounding of the Boeing planes through March 5. Southwest said their 737 Max fleet would return to service on March 6, which is around the one-year anniversary of a fatal Ethiopian Airlines crash on the 737 Max plane. Just months earlier, a Lion Air 737 Max flight also crashed in Indonesia—killing everyone on board. Over 300 people died in both crashes, and the fatalities caused a widespread grounding of the planes and investigations into its mechanisms.