diff --git a/CHANGELOG.md b/CHANGELOG.md
index c28c82b5..cfb790ee 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,7 @@
 
 ### 3.11.0 (November 7, 2016)
 
-* Allow `logEvent` with a custom timestamp. If the timestamp value is `nil`, then the event is timestamped with the current time. See [iOS documentation](https://rawgit.com/amplitude/Amplitude-iOS/master/documentation/html/Classes/Amplitude.html#//api/name/logEvent:withEventProperties:withGroups:withTimestamp:outOfSession:) for more details.
+* Allow `logEvent` with a custom timestamp (milliseconds since epoch). If the timestamp value is `nil`, then the event is timestamped with the current time. If setting a custom timesatmp, you should use `[NSNumber numberWithLongLong:milliseconds]`. See [iOS documentation](https://rawgit.com/amplitude/Amplitude-iOS/master/documentation/html/Classes/Amplitude.html#//api/name/logEvent:withEventProperties:withGroups:withTimestamp:outOfSession:) for more details.
 
 ### 3.10.1 (October 31, 2016)