Boeing says it has finished with its updates to the flight-control software implicated in two deadly crashes involving its 737 Max, moving a step closer to getting the plane back in the sky. Aviation regulators still have more questions about how pilots interact with the plane’s controls under different circumstances, and Boeing says it is providing that information. The next major step is a certification flight with Federal Aviation Administration representatives on board. Boeing said Thursday that flight has not yet been scheduled. In crashes in Indonesia in October and Ethiopia in March, an automated system called MCAS mistakenly turned the noses of the planes down in response to faulty readings from a single sensor. Pilots were unable to recover; 346 people died.