In the open recruitment process, how many minutes before the interview should candidates draw lots to determine the interview order?

Take the civil service exam as an example. There will be a time between the time you are notified of arriving at the interview location and the start time of the exam (interview). For example, you will be notified to arrive at the waiting area (a large room) of the examination room at 8 o'clock and start at 9 o'clock. For interviews, the lottery usually starts at 8:15 (lateness is allowed). After the lottery is completed, you will wait in the examination room lounge and are not allowed to leave. Until it's your turn for the interview, you will get your results on the spot after the interview, and then you will be asked to leave the examination room directly and check your interview ranking online.