diff --git a/docs/en/ml/calendars.asciidoc b/docs/en/ml/calendars.asciidoc
index 9a9590d1d47..117ed5cb42c 100644
--- a/docs/en/ml/calendars.asciidoc
+++ b/docs/en/ml/calendars.asciidoc
@@ -26,6 +26,8 @@ iCalendar (`.ics`) file in {kib} or a JSON file in the
 [NOTE]
 --
 
+* You must identify scheduled events before your job analyzes the data for that
+time period. Machine learning results are not updated retroactively.
 * If your iCalendar file contains recurring events, only the first occurrence is
 imported.
 * Bucket results are generated during scheduled events but they have an