I’ve been scratching through a number of feeds, all buses so far, and have noticed that the
stop_time_update entries are usually only for future stops, but not always, so I’d like to understand what’s happening.
Is it safe to assume that a stop time update with arrival/departure time that is less than the trip update timestamp is an event that has happened in the past? i.e. that the bus has arrived / departed?
Under what conditions are
stop_time_updatesomitted from the updates? For the most part it appears that any past data is omitted, is that a fair assumption? I’m thinking not, as I’ve found some records that contradict this, but I’d like to understand if they accurately reflect past data, or if they’re erroneous.
There are updates with
schedule_relationship: NO_DATAfor each stop, and missing the trip update timestamp. The spec seems to state that NO_DATA should reflect partial updates (e.g. the next 3 stops of 10) but these are full updates. When making assertions such as “this bus is on time”, should these records be ignored?