Virtually all larger delays from the VBB live map are missing in the GTFS-RT stream #6
Description
Thank you for providing the GTFS-RT stream, this is highly appreciated!
I have been using this stream for several months now, and I have noticed that there are suspiciously few delays in the data.
For example, consider the following screenshot of the VBB live map, showing the Berlin tram network this morning, which shows several trams having delays > 2 minutes, sometimes over 10 minutes:
The same state on TRAVIC, based on the VBB production GTFS-RT stream:
Most of the vehicles have a delay of 0 seconds at all stops, with only a handful of vehicles having delays of around 1 or 2 minutes. All the larger delays shown on the live map are missing in the GTFS-RT stream. The same is true for subways and busses. For example, at the moment U3 to Krumme Lanke has a scheduled departure from Gleisdreieck at 11:06 and the live map shows a delay of 20 minutes. The GTFS-RT stream shows it as perfectly punctual.
This has been the case since at least the summer of 2025. Is this a known issue? I can imagine some synchronization issue, with the GTFS-RT-stream only including very old optimistic delay data, collected before the trips actually started.
Is there maybe an alternative and more reliable data source (VDV-x, TRIAS, SIRI, etc.) under the same license? Shouldn't it be possible to just create a GTFS-RT-stream directly from polling the VBB live map data every 60 seconds? The combination stop id + line name + headsign + departure time should be unique across the entire feed.