each day corresponds to a time on the clock. The clock is cyclical and is a way of linking posts and information. Anons put this together based on Q comments such as "star the clock" and "rewind the clock".  Usually the same second on the clock has a running theme. Sometimes the mirror of the clock also relates (maybe always- I haven't looked at that piece closely). We can use this info to look ahead a bit as well to see what's coming.