A fare only on a day the nonstop flies

A reader wrote in about Boston to Terceira. The Azores Flights calendar showed a price several days a week, and the nonstop flies once a week.

The fare cache the site reads holds no stop data. Ask it for a nonstop pair and it answers with whatever itinerary is cheapest, connections included, filed under the pair that was asked for. Production showed near daily prices on all 36 directional routes. Most of those days were connections.

The fix reads the airline’s own public timetable and shows a fare only on a day a nonstop is scheduled. A round trip needs both days to qualify. The filter sits at the one place fares are read, so it covers the boards, the calendar, the landing page, the social cards, llms.txt, the sitemap, the weekly reports including closed weeks, the Monday email and the alerts.

The timetable is now its own upstream. It refreshes nightly in full and at midday for the next two weeks, on its own single thread lane. Five failed weeks in a row send a message. After 72 hours a stale banner goes up, and the Monday email is held until the timetable is fresh, because a fare filtered against a stale schedule is the original bug again.

Three published weekly reports got a correction note. Lisbon to Santa Maria came off the list entirely, since no sampled week had a nonstop in either direction.

The same day another reader pointed out a nonstop from Paris the site did not list. A sweep checked every island against every airport the airline flies from, sampling six weeks across a year. It found Paris to Ponta Delgada, seasonal, three days a week, which the cache only returns under the city code PAR. It found Funchal to Terceira. Bermuda and Oakland turned out to have cached fares but no nonstop at all, and four islands only fly inside the Azores.

A monthly audit now reruns that sweep and reports any nonstop the list is missing. The suite went to 1,452 examples.