V2 - GetFlightID seems unstable

FlightAware AeroAPI
1

If I call AirlineFlightSchedules for departing flights out of Austin for today and then try to get all those flightid’s using the ident and departuretime from the former call, many are missing.

error=NO_DATA flight not found

Some examples:

departureTime=1587329400&ident=SAS3902
departureTime=1587329400&ident=UAL734
departureTime=1587330300&ident=ASA3354
departureTime=1587330600&ident=ANZ6358
departureTime=1587330600&ident=UAL6061
departureTime=1587330600&ident=ACA5190
departureTime=1587330600&ident=DLH8635
departureTime=1587331800&ident=WJA6462
departureTime=1587331800&ident=AMX3142

Is this because many flights are getting cancelled now?

2

These all represent flights that are no longer scheduled. No faFlightID exists since there was never a filed flight plan. Unfortunately the advanced schedule data doesn’t capture mid-cycle changes to planning, so it’s possible for stale results to exist.

For upcoming flights in the near (up to 48 hours in advance) the Scheduled endpoint may be more useful since it will return flights with a filed plan. It will still return a filed_departuretime and ident that can be used in GetFlightID

3

So faFlightId are only issued when a flight plan is filed. So if I were to go into the future for AirlineFlightSchedules, I would get no faFlightIds returned? What is the windows for when faFlightIds are issued?