The possible reasons for this situation are as follows:

1. Peak holiday travel period: At this time, many people choose to travel by plane to meet their leisure and entertainment needs.

2. Frequent business activities: If business activities are frequent during this period, many business travelers will need to travel by air, and airlines will also increase the number of flights based on market demand.

3. Increase in freight demand: During holidays or e-commerce events, freight demand may increase significantly as goods need to be transported between cities, which may also lead to an increase in the number of aircraft.

4. Airport capacity restrictions: If some airports have limited capacity and cannot accommodate too many flights taking off and landing at the same time, airlines may adjust the number of flights based on airport capacity.

5. Aircraft failure or maintenance needs: Sometimes, some aircraft may need to be replaced due to failure or maintenance needs, which will also lead to a temporary increase in the number of aircraft.