diff --git a/RELEASE-NOTES-1.41 b/RELEASE-NOTES-1.41
index 990a7c3856f..b9e4db30e61 100644
--- a/RELEASE-NOTES-1.41
+++ b/RELEASE-NOTES-1.41
@@ -627,6 +627,7 @@ because of Phabricator reports.
   - SiteStatsInit -> MediaWiki\SiteStats\SiteStatsInit
   - MediaWiki\ExtensionInfo -> MediaWiki\Utils\ExtensionInfo
   - GitInfo -> MediaWiki\Utils\GitInfo
+  - MWTimestamp -> MediaWiki\Utils\MWTimestamp
 * The following methods, previously deprecated, now emit deprecation warnings:
   - ConfigFactory::getDefaultInstance(), deprecated since 1.27
   - AbstractContent::getNativeData(), deprecated since 1.33
diff --git a/includes/utils/MWTimestamp.php b/includes/utils/MWTimestamp.php
index dd824f22b85..4d69e533daf 100644
--- a/includes/utils/MWTimestamp.php
+++ b/includes/utils/MWTimestamp.php
@@ -156,4 +156,7 @@ class MWTimestamp extends ConvertibleTimestamp {
 	}
 }
 
+/**
+ * @deprecated since 1.41
+ */
 class_alias( MWTimestamp::class, 'MWTimestamp' );