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Flight disruptions that have marred air travel for millions of people in recent weeks could continue even after the government shutdown ends, airlines warned late Monday. The Senate on Monday night passed a bill that could end the longest federal government shutdown in history, sending it to the House for a vote. That vote came as staffing shortages of air traffic controllers, who are required to work without their regular paychecks in the shutdown, have delayed or canceled thousands of flights, with issues worsening in recent days. More than 5 million travelers have been affected by airline staffing issues since the shutdown began on Oct. 1, Airlines for America, a lobbying group for airlines including Delta Air Lines , United Airlines , American Airlines , Southwest Airlines , said late Monday. The disruptions have sent some passengers looking for alternatives, from buses to rental cars and even private jets. Last Friday, the Trump administration started requiring commercial airlines to cut 4% of their domestic flights at 40 busy U.S. airports, with larger cuts on the way, as officials blamed the strain on air traffic controllers. But even if the House passes the bill that will fund the federal government through January, it will take airlines time to readjust. "Airlines' reduced flight schedules cannot immediately bounce back to full capacity right after the government reopens," Airlines for America said in a statement. "It will take time, and there will be residual effects for days. With the Thanksgiving travel period beginning next week and the busy shipping season around the corner, the time to act is now to help mitigate any further impacts to Americans." Aviation groups have said that record numbers of travelers are expected for the Thanksgiving period, with the holiday just over two weeks away.