Echo Protocol

In the low-orbit system where humans observe the universe, a piece of data that does not belong to any known model was discovered. It's called a "delay table." This table does not predict the future, nor does it record the past, but quietly arranges the order in which each civilization is responded to. As the scope of observation expands, humans gradually realize: The universe is not silent, but delayed in responding. Some civilizations have known about this for a long time and have chosen to remain silent. When the echo begins to shift, When silence no longer means nothingness, Humanity must face a problem If the response never comes too late, are we still an established civilization?