A record 65 million trips are expected to be made by air across China during the Spring Festival travel rush, up by 10 percent on last year, the civil aviation watchdog said on Jan 17.

“The demand is great,” said Liu Feng, director of the Department of Transport from the Civil Aviation Administration of China, adding that growth has remained steady.

Tickets to big cities where many migrant workers are gathered and tourism destinations in China’s northernmost and southernmost regions will be sought after due to the high seasonal demand, Liu said.

The 40-day travel rush will begin on Feb 1 and end on March 12.

The peak will come toward the end of the period when three population streams coincide with possible weather extremes, he said.

The three population streams are migrant workers returning to work from their homes, students going back to school and politicians heading to Beijing ahead of the annual national political sessions－the National People’s Congress and the Chinese People’s Political Consultative Conference.

Airlines are required to adjust flight schedules based on market needs and optimize schedules and flight modes, to cater to travelers’ requirements, he said, adding that backup plans are also required to prevent long delays in the event of mechanical problems.

“Airlines are encouraged to change to widebody airplanes on popular routes,” said Tian Zhencai, deputy director of the administration’s operations and monitoring center.

Plan adjustments will be made when extreme weather occurs and the civil aviation department will coordinate with military aviation to open temporary air routes to increase air space for civil aviation, Tian said.

This year’s Spring Festival holiday runs from Feb 15 to 21. Most people return home for family reunions during the most important festival in China. In recent years, people have also taken the long holiday as a chance to travel, pushing up demand for tickets and prices.

The punctuality rate for flights in December was 88.3 percent, the best since June 2003, Tian said.

He also said that cold weather and poor visibility could affect punctuality in mid and late January.

The punctuality rate in 2017 was 71.7 percent, a drop of more than 5 percentage points compared with 2016. The main reasons for the decline were an increase in the number of flights, extreme weather and airspace activity.

The administration has set a goal for national flight punctuality of no less than 75 percent this year.

“The civil aviation industry will focus on improving quality and efficiency to enhance the flight punctuality rate,” Feng Zhenglin, head of the Civil Aviation Administration of China, said at a conference in December.