# description
A headway-based service specification indicating how often a vehicle runs on a route within a given time window.

# properties.headwaySecs.description
Time in seconds between consecutive vehicle departures

# properties.exactTimes.description
Whether departures are at exact scheduled times (true) or headway-based (false)

# properties.startTime.description
Time at which this frequency period begins (HH:MM:SS)

# properties.endTime.description
Time at which this frequency period ends (HH:MM:SS)