The SCU 2026 synthesis of four prior studies identifies six independent evidence streams all pointing to the same operational profile: (1) Near-total absence of simultaneous multi-site incursions across 30 years — even during peak waves like July 1952; (2) Staggered redeployment — activity progresses site-to-site in tight temporal sequences, never appearing in parallel; (3) Sustained disproportionate focus on nuclear infrastructure — strategic prioritization, not random distribution; (4) Behavioral adaptation — shifted from overt daylight displays to predominantly nocturnal low-visibility profile over the study period; (5) Selective visibility control — craft illuminate themselves at distance, extinguish lights when interceptors approach, suggesting both operational restraint AND possible vulnerability; (6) Limited platform diversity — multiple shapes present but never in large simultaneous formations. These six lines of evidence together rule out both large-scale invasion scenarios and random/natural phenomena. The authors conclude a permanent local base of operations is “not only plausible but likely essential” for sustained autonomous operations.