DALLAS (AP) — United Airlines is raising its estimate of third-quarter revenue because of strong demand for tickets over the summer vacation season. The Chicago airline said Wednesday that revenue will be 12% higher than in the same quarter of 2019. That’s one percentage point better than previously forecast. Meanwhile, United says it will suspend its limited service at New York’s JFK Airport unless it can get more takeoff and landing rights there. The airline says JFK has room to grow because of runway and taxiway improvements. United operates just two daily flights to each Los Angeles and San Francisco from JFK.