diff --git a/bin/check-source b/bin/check-source
index 26717a7d..f975eb0a 100755
--- a/bin/check-source
+++ b/bin/check-source
@@ -2,7 +2,7 @@
 #
 # This source file is part of the Swift.org open source project
 #
-# Copyright (c) 2021 Apple Inc. and the Swift project authors
+# Copyright (c) 2021-2024 Apple Inc. and the Swift project authors
 # Licensed under Apache License v2.0 with Runtime Library Exception
 #
 # See https://swift.org/LICENSE.txt for license information
@@ -18,7 +18,7 @@ here="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
 function replace_acceptable_years() {
     # this needs to replace all acceptable forms with 'YEARS'
-    sed -e 's/20[12][7890123]-20[12][890123]/YEARS/' -e 's/20[12][890123]/YEARS/'
+    sed -e 's/20[12][78901234]-20[12][8901234]/YEARS/' -e 's/20[12][8901234]/YEARS/'
 }
 
 printf "=> Checking for unacceptable language… "