[DOCS] Clarified use of historical events (elastic/x-pack-elasticsearch#3737)
Original commit: elastic/x-pack-elasticsearch@79095ee59a5cffce2c7c77e5251844f4ab2dc0bd
@@ -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
