Why do you have to stay in a hotel for three days after coming back from Tongliao, Inner Mongolia for five days?

The epidemic situation in COVID-19 is changing every day. The establishment of Zhelimu League, the predecessor of Tongliao City, began in the early Qing Dynasty. Its geographical scope starts from the Taoer River and Nenjiang River basins south of Suoyuerji Mountain in the north, and reaches the East-West Liaohe River basin and the Yangximu River in Uhannad Mountain in the south. Come back from Tongliao, Inner Mongolia for five days and stay in a hotel for three days. The epidemic situation in COVID-19 is changing every day. Some people originally came back from low-risk areas and only needed to be isolated at home for seven days as required. On the fourth day of isolation, the original low-risk area suddenly upgraded to a medium-high risk area. At this time, the isolation requirement is changed from home isolation to centralized isolation. Because they have been isolated at home for four days, you only need to concentrate on isolation for three days.