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Compare domestic round-trip fares 21 vs 54 days ahead on the 10 busiest U.S. routes using live, like-for-like totals instead of headline prices. Independent technical note mirroring the canonical version: https://sarahcheapflights.com/blog/booking-21-vs-54-days-ahead-verify-domestic-round-trip-fares.php
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Cooper Rhodes (2026) studied this question.
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