TRAPPIST Star System
Age: 7 Billion Years~
Planets in Habitable Zone: 3-4
Very Earth-like Planet: 1

So, this bad boy has 3 Billion Years of age on us.
Any signs of intelligence there, with what we know so far? Surely we'd be erecting Dyson objects in this timeframe.
This is one of the top targets for JWST investigation after our boy JWST fires up the scope.

What will we look for? What "could" we expect, if we assume that TRAPPIST 1e (The Earthlike one, had intelligent life.)

Let's find some space bros.