diff --git a/tests/NATS.Server.Tests/JetStream/Cluster/JetStreamClusterFailoverTests.cs b/tests/NATS.Server.Tests/JetStream/Cluster/JetStreamClusterFailoverTests.cs
index 9d2309a..6d49067 100644
--- a/tests/NATS.Server.Tests/JetStream/Cluster/JetStreamClusterFailoverTests.cs
+++ b/tests/NATS.Server.Tests/JetStream/Cluster/JetStreamClusterFailoverTests.cs
@@ -519,7 +519,14 @@ internal sealed class ClusterFailoverFixture : IAsyncDisposable
         => _consumerManager.FetchAsync(stream, durableName, batch, _streamManager, default).AsTask();
 
     public Task<JetStreamApiResponse> RequestAsync(string subject, string payload)
-        => Task.FromResult(_router.Route(subject, Encoding.UTF8.GetBytes(payload)));
+    {
+        var response = _router.Route(subject, Encoding.UTF8.GetBytes(payload));
+
+        if (subject.Equals(JetStreamApiSubjects.MetaLeaderStepdown, StringComparison.Ordinal) && response.Success)
+            _metaGroup.BecomeLeader();
+
+        return Task.FromResult(response);
+    }
 
     public ValueTask DisposeAsync() => ValueTask.CompletedTask;
 }
diff --git a/tests/NATS.Server.Tests/JetStream/Cluster/JetStreamClusterFixture.cs b/tests/NATS.Server.Tests/JetStream/Cluster/JetStreamClusterFixture.cs
index 7ed6774..76dbdb2 100644
--- a/tests/NATS.Server.Tests/JetStream/Cluster/JetStreamClusterFixture.cs
+++ b/tests/NATS.Server.Tests/JetStream/Cluster/JetStreamClusterFixture.cs
@@ -223,7 +223,17 @@ internal sealed class JetStreamClusterFixture : IAsyncDisposable
     /// Go ref: nc.Request() in cluster test helpers.
     /// </summary>
     public Task<JetStreamApiResponse> RequestAsync(string subject, string payload)
-        => Task.FromResult(_router.Route(subject, Encoding.UTF8.GetBytes(payload)));
+    {
+        var response = _router.Route(subject, Encoding.UTF8.GetBytes(payload));
+
+        // In a real cluster, after stepdown a new leader is elected.
+        // Simulate this node becoming the new leader so subsequent
+        // mutating operations through the router succeed.
+        if (subject.Equals(JetStreamApiSubjects.MetaLeaderStepdown, StringComparison.Ordinal) && response.Success)
+            _metaGroup.BecomeLeader();
+
+        return Task.FromResult(response);
+    }
 
     // ---------------------------------------------------------------
     // Leader operations
@@ -241,7 +251,13 @@ internal sealed class JetStreamClusterFixture : IAsyncDisposable
     /// Go ref: c.leader().Shutdown() in jetstream_helpers_test.go.
     /// </summary>
     public void StepDownMetaLeader()
-        => _metaGroup.StepDown();
+    {
+        _metaGroup.StepDown();
+        // In a real cluster, a new leader is elected after stepdown.
+        // Simulate this node becoming the new leader so subsequent
+        // mutating operations through the router succeed.
+        _metaGroup.BecomeLeader();
+    }
 
     /// <summary>
     /// Returns the current meta-group state snapshot.
diff --git a/tests/NATS.Server.Tests/JetStream/Cluster/LeaderFailoverParityTests.cs b/tests/NATS.Server.Tests/JetStream/Cluster/LeaderFailoverParityTests.cs
index d62504d..6ec9882 100644
--- a/tests/NATS.Server.Tests/JetStream/Cluster/LeaderFailoverParityTests.cs
+++ b/tests/NATS.Server.Tests/JetStream/Cluster/LeaderFailoverParityTests.cs
@@ -215,7 +215,14 @@ internal sealed class LeaderFailoverFixture : IAsyncDisposable
     public MetaGroupState? GetMetaState() => _streamManager.GetMetaState();
 
     public Task<JetStreamApiResponse> RequestAsync(string subject, string payload)
-        => Task.FromResult(_router.Route(subject, Encoding.UTF8.GetBytes(payload)));
+    {
+        var response = _router.Route(subject, Encoding.UTF8.GetBytes(payload));
+
+        if (subject.Equals(JetStreamApiSubjects.MetaLeaderStepdown, StringComparison.Ordinal) && response.Success)
+            _metaGroup.BecomeLeader();
+
+        return Task.FromResult(response);
+    }
 
     public ValueTask DisposeAsync() => ValueTask.CompletedTask;
 }