What is the highest state of space-time companion?

Hello, space-time companion is the definition of class C space-time companion: it means that the number used by the infected person stays in the same space-time grid (the range is 800 m * 800 m) * * for more than 14 minutes, and any number stays in the area for more than 30 hours in the last 14 days, and the screened number is judged as the space-time companion number. Or in the outdoor open space, the mobile phone number that has collided with the same base station within a certain distance within a specified time (for example, 10 minutes or more) is defined as the space-time companion that may be exposed. Measures for the management of spatio-temporal companions: In most areas, the screened spatio-temporal companions are given yellow health codes, suggesting that the first nucleic acid test is needed within 24 hours, and home health monitoring is implemented. The second nucleic acid test was carried out on the third day. If the result is negative, the community (village) can apply to cancel the yellow code. After receiving the decoding application, the community (village) will conduct a preliminary examination, and those who meet the requirements will be submitted to the district/county (city) level CDC and the district/county (county). There are also some cluster epidemic surveys with high transmission risk, which manage the detected spatio-temporal peers with reference to close contacts and implement centralized isolation and nucleic acid detection.