The reportingPeriodStart on a ReportPackage is the first day of the monitoring period mandated by your permit or work plan — for example, January 1 for an annual report or April 1 for a second-quarter report. Piper uses this date together with reportingPeriodEnd to filter which sampling events are available when you link events to the package via samplingEventIdsJson. Setting incorrect period boundaries risks including data from the wrong period in your regulatory submittal.
Technical section
Data model, API, and internals — visible to developers.