Southwest Airlines currently has a fleet coverage of 86.2% but has not yet equipped any aircraft with Starlink as of the latest update. The rollout status is 'rolling_out' with an announced start in summer 2026, and no confirmed observations or sightings on the PAE->DEN route. Given the fleet coverage is high but no aircraft are equipped yet, and no route-specific observations exist, the probability is anchored at 0.0. The rollout is upcoming, so no higher probability is justified at this time.