Such production issues can be detected after planes enter service and fixed during maintenance. In the past, Boeing was given latitude by the FAA to fix minor issues after the planes were carrying passengers, as long as the problems didn't pose immediate safety hazards. In the wake of two fatal 737 MAX crashes in 2018 and 2019, however, regulators are insisting that new Dreamliners match the plane maker's precise FAA-approved designs and comply with federal air-safety regulations before Boeing delivers the new jets. As a result, Boeing is currently stuck with more than $25 billion of undelivered planes, with some customers canceling orders and airlines having to cut flight schedules. The company is retooling its factory process and supply chain to make sure Dreamliners are built correctly the first time. Deliveries are expected to resume as soon as this summer, people familiar with the matter have said. In April, Boeing submitted a plan for FAA approval that would allow Dreamliner deliveries to resume.