The lastGeneratedAt timestamp on a CustomReport tells you how fresh the stored PDF is. If you updated data in Piper after the date shown here, the lastPdfBytes may be stale and you should regenerate the report before distributing it. This is especially important for monthly status summaries that go to clients — always check lastGeneratedAt before downloading and sending to ensure the PDF contains the most recent sampling results. Generating a new PDF updates lastGeneratedAt to the current time.
Technical section
Data model, API, and internals — visible to developers.