The Protobuf object to read from
The end position of the message in the buffer
OptionalstopThe replacement stop ID which will now be visited by the trip. May refer to a new stop added using a GTFS-RT Stop message, or to an existing stop defined in the GTFS-Static feed's stops.txt. The stop MUST have location_type=0 (routable stops).
OptionaltravelThe difference in seconds between the arrival time at this stop and the arrival time at the reference stop. The reference stop is the stop prior to start_stop_selector. If the modification begins at the first stop of the trip, then the first stop of the trip is the reference stop. This value MUST be monotonically increasing and may only be a negative number if the first stop of the original trip is the reference stop.
NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.