Task: Find the earliest one-way economy flight from San Francisco (SFO) to Seattle (SEA) on 2026-06-15.
Hint: Use one-way search, enter San Francisco (SFO) as the origin and Seattle (SEA) as the destination, choose 2026-06-15, choose economy, then compare the visible departure times manually.
Reference answer: United Airlines flight UA1681, Air Canada flight AC5009, departing 6:42 AM and arriving 3:53 PM, 1 stop, total travel time 9h 11m