diff --git a/fledge/tentative/join-leave-ad-interest-group.https.window.js b/fledge/tentative/join-leave-ad-interest-group.https.window.js
index 107bd3b815ada1b..c3c97d60c614424 100644
--- a/fledge/tentative/join-leave-ad-interest-group.https.window.js
+++ b/fledge/tentative/join-leave-ad-interest-group.https.window.js
@@ -481,14 +481,14 @@ const SIMPLE_JOIN_LEAVE_TEST_CASES = [
   { expectJoinSucces: true,
     expectLeaveSucces: true,
     interestGroup: { ...BASE_INTEREST_GROUP,
-      name: 'a'.repeat(1048524)
+      name: 'a'.repeat(1048520)
     },
     testCaseName: "Largest possible interest group dictionary",
   },
   { expectJoinSucces: false,
     expectLeaveSucces: true,
     interestGroup: { ...BASE_INTEREST_GROUP,
-      name: 'a'.repeat(1048525)
+      name: 'a'.repeat(1048521)
     },
     testCaseName: "Oversized interest group dictionary",
   },