diff --git a/App.xaml b/App.xaml
index 0acc91dc..29dca019 100644
--- a/App.xaml
+++ b/App.xaml
@@ -597,13 +597,6 @@
                                 <Setter TargetName="RowBorder" Property="Background" Value="#EAF2FF"/>
                                 <Setter TargetName="RowBorder" Property="BorderBrush" Value="#C7DAFF"/>
                             </Trigger>
-                            <!-- Runtime live-value edge highlight. This trigger is placed
-                                 after selection so a selected commissioning row still flashes. -->
-                            <DataTrigger Binding="{Binding IsRecentlyChanged}" Value="True">
-                                <Setter TargetName="RowBorder" Property="Background" Value="#FFF0A8"/>
-                                <Setter TargetName="RowBorder" Property="BorderBrush" Value="#F59E0B"/>
-                                <Setter TargetName="RowBorder" Property="BorderThickness" Value="4,1,1,1"/>
-                            </DataTrigger>
                         </ControlTemplate.Triggers>
                     </ControlTemplate>
                 </Setter.Value>
diff --git a/MainWindow.CommandPanelUx.cs b/MainWindow.CommandPanelUx.cs
index 4589d1a6..0b78eaf2 100644
--- a/MainWindow.CommandPanelUx.cs
+++ b/MainWindow.CommandPanelUx.cs
@@ -7,6 +7,7 @@
 using System.Windows.Media;
 using System.Windows.Threading;
 using ArIED61850Tester.Models;
+using ArIED61850Tester.Services;
 
 namespace ArIED61850Tester;
 
@@ -31,7 +32,18 @@ public object Convert(object[] values, Type targetType, object parameter, Cultur
             var testMode = values.ElementAtOrDefault(1) is true;
             var busy = values.ElementAtOrDefault(2) is true;
             var supportsOperate = values.ElementAtOrDefault(3) is true;
-            return (liveArmed || testMode) && supportsOperate && !busy;
+            var current = values.ElementAtOrDefault(4)?.ToString() ?? string.Empty;
+            var command = parameter?.ToString() ?? string.Empty;
+            return (liveArmed || testMode) && supportsOperate && !busy && (testMode || !AlreadyActive(command, current));
+        }
+
+        private static bool AlreadyActive(string command, string current)
+        {
+            if (string.IsNullOrWhiteSpace(command) || string.IsNullOrWhiteSpace(current) || current.Trim() == "-") return false;
+            if (Iec61850ValueFormatter.TryNormalizeDbpos(command, out var requested) &&
+                Iec61850ValueFormatter.TryNormalizeDbpos(current, out var actual)) return requested == actual;
+            if (bool.TryParse(command, out var requestedBool) && bool.TryParse(current, out var actualBool)) return requestedBool == actualBool;
+            return command.Trim().Equals(current.Trim(), StringComparison.OrdinalIgnoreCase);
         }
 
         public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
@@ -51,17 +63,10 @@ public object Convert(object value, Type targetType, object parameter, CultureIn
                 return "Status only";
             }
 
-            if (text.Contains("select before operate", StringComparison.OrdinalIgnoreCase) ||
-                text.Contains("SBO", StringComparison.OrdinalIgnoreCase))
-            {
-                return "SBO";
-            }
-
-            if (text.Contains("direct operate", StringComparison.OrdinalIgnoreCase) ||
-                text.Contains("(DO)", StringComparison.OrdinalIgnoreCase))
-            {
-                return "DO";
-            }
+            if ((text.Contains("select before operate", StringComparison.OrdinalIgnoreCase) || text.Contains("SBO", StringComparison.OrdinalIgnoreCase)) && text.Contains("enhanced", StringComparison.OrdinalIgnoreCase)) return "SBO • Enhanced security";
+            if (text.Contains("select before operate", StringComparison.OrdinalIgnoreCase) || text.Contains("SBO", StringComparison.OrdinalIgnoreCase)) return "SBO • Normal security";
+            if ((text.Contains("direct operate", StringComparison.OrdinalIgnoreCase) || text.Contains("(DO)", StringComparison.OrdinalIgnoreCase)) && text.Contains("enhanced", StringComparison.OrdinalIgnoreCase)) return "Direct • Enhanced security";
+            if (text.Contains("direct operate", StringComparison.OrdinalIgnoreCase) || text.Contains("(DO)", StringComparison.OrdinalIgnoreCase)) return "Direct • Normal security";
 
             if (text.Contains("auto-detect", StringComparison.OrdinalIgnoreCase) ||
                 string.IsNullOrWhiteSpace(text))
@@ -105,7 +110,7 @@ private void InstallCommandPanelUx()
 
         _commandPanelUxTimer = new DispatcherTimer(DispatcherPriority.Background)
         {
-            Interval = TimeSpan.FromMilliseconds(500)
+            Interval = TimeSpan.FromMilliseconds(1500)
         };
         _commandPanelUxTimer.Tick += CommandPanelUxTimer_Tick;
         _commandPanelUxTimer.Start();
@@ -210,12 +215,14 @@ private void ConfigureCommandPanelButton(Button button)
         var enabledBinding = new MultiBinding
         {
             Converter = CommandButtonEnabledConverter.Instance,
+            ConverterParameter = content,
             Mode = BindingMode.OneWay
         };
         enabledBinding.Bindings.Add(new Binding(nameof(LiveControlArmed)) { Source = this });
         enabledBinding.Bindings.Add(new Binding(nameof(CommandTestMode)) { Source = this });
         enabledBinding.Bindings.Add(new Binding(nameof(SignalDefinition.ControlIsBusy)));
         enabledBinding.Bindings.Add(new Binding(nameof(SignalDefinition.ControlSupportsOperate)));
+        enabledBinding.Bindings.Add(new Binding(nameof(SignalDefinition.ControlCurrentValue)));
         BindingOperations.SetBinding(button, UIElement.IsEnabledProperty, enabledBinding);
 
         _configuredCommandButtons.Add(button, new Marker());
diff --git a/MainWindow.xaml b/MainWindow.xaml
index 95dbd49c..dd34dc31 100644
--- a/MainWindow.xaml
+++ b/MainWindow.xaml
@@ -111,20 +111,17 @@
             <TabItem Header="IEC 61850 Explorer">
                 <Grid>
                     <Grid.ColumnDefinitions>
-                        <ColumnDefinition Width="250"/>
+                        <ColumnDefinition Width="258"/>
                         <ColumnDefinition Width="12"/>
                         <ColumnDefinition Width="*"/>
                     </Grid.ColumnDefinitions>
 
                     <Border Grid.Column="0" Style="{StaticResource Card}" Padding="10">
                         <DockPanel>
-                            <Grid DockPanel.Dock="Top" Margin="0,0,0,10">
-                                <StackPanel>
-                                    <StackPanel Orientation="Horizontal">
-                                        <Ellipse Width="8" Height="8" Fill="{StaticResource Accent}" Margin="0,0,8,0" VerticalAlignment="Center"/>
-                                        <TextBlock Text="IED Explorer" FontSize="15.5" FontWeight="SemiBold" Foreground="{StaticResource Ink}"/>
-                                    </StackPanel>
-                                    <TextBlock Text="Independent MMS session per IED" FontSize="11.8" Foreground="{StaticResource Muted}" Margin="16,3,0,0"/>
+                            <Grid DockPanel.Dock="Top" Margin="0,0,0,8">
+                                <StackPanel Orientation="Horizontal">
+                                    <Ellipse Width="8" Height="8" Fill="{StaticResource Accent}" Margin="0,0,8,0" VerticalAlignment="Center"/>
+                                    <TextBlock Text="IED Explorer" FontSize="15.5" FontWeight="SemiBold" Foreground="{StaticResource Ink}"/>
                                 </StackPanel>
                             </Grid>
 
@@ -136,13 +133,13 @@
                                 <Grid>
                                     <Grid.ColumnDefinitions>
                                         <ColumnDefinition Width="*"/>
-                                        <ColumnDefinition Width="8"/>
+                                        <ColumnDefinition Width="6"/>
                                         <ColumnDefinition Width="*"/>
                                     </Grid.ColumnDefinitions>
-                                    <Button Grid.Column="0" Click="ConnectAllIeds_Click" Style="{StaticResource SoftButton}"
+                                    <Button Grid.Column="0" Click="ConnectAllIeds_Click" Style="{StaticResource SoftButton}" Padding="8,7" FontSize="11.5"
                                             ToolTip="Fast-connect every saved IED and start live monitoring for its saved selections">
                                         <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
-                                            <Viewbox Width="14" Height="14" Margin="0,0,6,0">
+                                            <Viewbox Width="13" Height="13" Margin="0,0,4,0">
                                                 <Canvas Width="24" Height="24">
                                                     <Path Data="M5,3 L19,12 L5,21 Z" Stroke="#16A34A" StrokeThickness="2" StrokeLineJoin="Round" Fill="Transparent"/>
                                                 </Canvas>
@@ -150,7 +147,7 @@
                                             <TextBlock Text="Connect All" FontWeight="SemiBold"/>
                                         </StackPanel>
                                     </Button>
-                                    <Button Grid.Column="2" Click="AddRelay_Click" Style="{StaticResource PrimaryButton}"
+                                    <Button Grid.Column="2" Click="AddRelay_Click" Style="{StaticResource PrimaryButton}" Padding="8,7" FontSize="11.5"
                                             ToolTip="Add another IEC 61850 IED">
                                         <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
                                             <TextBlock Text="＋" FontSize="15" FontWeight="SemiBold" Margin="0,-1,5,0"/>
@@ -173,7 +170,7 @@
                                         <Setter Property="Template">
                                             <Setter.Value>
                                                 <ControlTemplate TargetType="ListBoxItem">
-                                                    <Border x:Name="Card" Background="White" BorderBrush="{StaticResource Line}" BorderThickness="1" CornerRadius="15" Padding="10">
+                                                    <Border x:Name="Card" Background="White" BorderBrush="{StaticResource Line}" BorderThickness="1" CornerRadius="14" Padding="8">
                                                         <ContentPresenter/>
                                                     </Border>
                                                     <ControlTemplate.Triggers>
@@ -192,19 +189,19 @@
                                 </ListBox.ItemContainerStyle>
                                 <ListBox.ItemTemplate>
                                     <DataTemplate>
-                                        <Grid MinHeight="86">
+                                        <Grid MinHeight="72">
                                             <Grid x:Name="CardContent">
                                                 <Grid.RowDefinitions>
                                                     <RowDefinition Height="Auto"/>
                                                     <RowDefinition Height="Auto"/>
                                                 </Grid.RowDefinitions>
                                                 <Grid.ColumnDefinitions>
-                                                    <ColumnDefinition Width="64"/>
+                                                    <ColumnDefinition Width="66"/>
                                                     <ColumnDefinition Width="*"/>
                                                 </Grid.ColumnDefinitions>
                                                 <!-- Large borderless relay / BCU icon; icon color is the connection state. -->
-                                      <Grid Grid.Row="0" Grid.RowSpan="2" Grid.Column="0" Width="58" Height="58" Margin="0,-2,6,0" VerticalAlignment="Top" Panel.ZIndex="2">
-                                          <Viewbox Width="55" Height="55" HorizontalAlignment="Center" VerticalAlignment="Center">
+                                      <Grid Grid.Row="0" Grid.RowSpan="2" Grid.Column="0" Width="62" Height="62" Margin="0,0,4,0" VerticalAlignment="Center" Panel.ZIndex="2">
+                                          <Viewbox Width="60" Height="60" HorizontalAlignment="Center" VerticalAlignment="Center">
                                               <Path x:Name="RelayDeviceIcon" Data="M 2 0 L 2 20 L 18 20 L 18 0 L 2 0 z M 3 1 L 17 1 L 17 19 L 3 19 L 3 1 z M 5 3 L 5 7 L 15 7 L 15 3 L 5 3 z M 6 4 L 14 4 L 14 6 L 6 6 L 6 4 z M 5 10 L 5 11 L 7 11 L 7 10 L 5 10 z M 9 10 L 9 11 L 11 11 L 11 10 L 9 10 z M 13 10 L 13 11 L 15 11 L 15 10 L 13 10 z M 5 13 L 5 14 L 7 14 L 7 13 L 5 13 z M 9 13 L 9 14 L 11 14 L 11 13 L 9 13 z M 13 13 L 13 14 L 15 14 L 15 13 L 13 13 z M 5 16 L 5 17 L 7 17 L 7 16 L 5 16 z M 9 16 L 9 17 L 11 17 L 11 16 L 9 16 z M 13 16 L 13 17 L 15 17 L 15 16 L 13 16 z" Fill="#EF4444" Stretch="Uniform">
                                                   <Path.Effect><DropShadowEffect BlurRadius="14" ShadowDepth="0" Opacity="0.58" Color="#EF4444"/></Path.Effect>
                                               </Path>
@@ -221,7 +218,7 @@
 
                                                 <!-- Direct, unobstructed hit targets below the IP address. -->
                                                 <StackPanel Grid.Row="1" Grid.Column="1" Orientation="Horizontal"
-                                                            HorizontalAlignment="Left" Margin="0,7,0,0" Panel.ZIndex="10">
+                                                            HorizontalAlignment="Left" Margin="0,4,0,0" Panel.ZIndex="10">
                                                     <Button Style="{StaticResource IedIconButton}" Tag="{Binding}" Click="IedPlayAction_Click"
                                                             IsEnabled="{Binding CanPlayAction}" ToolTip="{Binding PlayToolTip}">
                                                         <Viewbox Width="16" Height="16"><Canvas Width="24" Height="24"><Path Data="M6,3 L20,12 L6,21 Z" Stroke="#16A34A" StrokeThickness="2" StrokeLineJoin="Round" Fill="Transparent"/></Canvas></Viewbox>
@@ -361,12 +358,12 @@
                                             </Style>
                                         </DataGrid.CellStyle>
                                         <DataGrid.Columns>
-                                            <DataGridTextColumn Header="Signal" Binding="{Binding SignalName}" Width="220*" MinWidth="175"/>
-                                            <DataGridTextColumn Header="IEC Telegram" Binding="{Binding IecTelegram}" Width="320*" MinWidth="250"/>
-                                            <DataGridTextColumn Header="Value" Binding="{Binding Value}" Width="120*" MinWidth="100"/>
-                                            <DataGridTextColumn Header="Quality" Binding="{Binding Quality}" Width="150*" MinWidth="125"/>
-                                            <DataGridTextColumn Header="IED Timestamp" Binding="{Binding DeviceTimestamp}" Width="185*" MinWidth="150"/>
-                                            <DataGridTextColumn Header="Acquisition" Binding="{Binding SourceMode}" Width="190*" MinWidth="160"/>
+                                            <DataGridTextColumn Header="Signal" Binding="{Binding SignalName}" Width="1.05*" MinWidth="145"/>
+                                            <DataGridTextColumn Header="IEC Telegram" Binding="{Binding IecTelegram}" Width="1.55*" MinWidth="205"/>
+                                            <DataGridTextColumn Header="Value" Binding="{Binding Value}" Width="0.8*" MinWidth="125"/>
+                                            <DataGridTextColumn Header="Quality" Binding="{Binding Quality}" Width="0.72*" MinWidth="105"/>
+                                            <DataGridTextColumn Header="IED Timestamp" Binding="{Binding DeviceTimestamp}" Width="1.05*" MinWidth="155"/>
+                                            <DataGridTextColumn Header="Acquisition" Binding="{Binding SourceMode}" Width="1.05*" MinWidth="150"/>
                                         </DataGrid.Columns>
                                     </DataGrid>
 
@@ -425,8 +422,8 @@
                                                       VirtualizingPanel.IsVirtualizing="True" VirtualizingPanel.VirtualizationMode="Recycling"
                                                       ScrollViewer.CanContentScroll="True" ScrollViewer.HorizontalScrollBarVisibility="Auto">
                                                 <DataGrid.Columns>
-                                                    <DataGridTextColumn Header="IEC Telegram" Binding="{Binding DisplayReference}" Width="280" IsReadOnly="True"/>
-                                                    <DataGridTemplateColumn Header="Value" Width="115">
+                                                    <DataGridTextColumn Header="IEC Telegram" Binding="{Binding DisplayReference}" Width="2.1*" MinWidth="210" IsReadOnly="True"/>
+                                                    <DataGridTemplateColumn Header="Value" Width="0.85*" MinWidth="105">
                                                         <DataGridTemplateColumn.CellTemplate>
                                                             <DataTemplate>
                                                                 <Border Padding="9,5" CornerRadius="10" HorizontalAlignment="Left" MinWidth="76">
@@ -467,9 +464,9 @@
                                                             </DataTemplate>
                                                         </DataGridTemplateColumn.CellTemplate>
                                                     </DataGridTemplateColumn>
-                                                    <DataGridTextColumn Header="CDC / Type" Binding="{Binding ControlCdc}" Width="105" IsReadOnly="True"/>
-                                                    <DataGridTextColumn Header="Control model" Binding="{Binding ControlModelText}" Width="210" IsReadOnly="True"/>
-                                                    <DataGridTemplateColumn Header="Control" Width="*" MinWidth="220">
+                                                    <DataGridTextColumn Header="CDC / Type" Binding="{Binding ControlCdc}" Width="0.72*" MinWidth="88" IsReadOnly="True"/>
+                                                    <DataGridTextColumn Header="Control model" Binding="{Binding ControlModelText}" Width="1.35*" MinWidth="175" IsReadOnly="True"/>
+                                                    <DataGridTemplateColumn Header="Control" Width="1.45*" MinWidth="200">
                                                         <DataGridTemplateColumn.CellTemplate>
                                                             <DataTemplate>
                                                                 <StackPanel Margin="0,3">
diff --git a/MainWindow.xaml.cs b/MainWindow.xaml.cs
index 9e0b2ca5..b1678f85 100644
--- a/MainWindow.xaml.cs
+++ b/MainWindow.xaml.cs
@@ -688,7 +688,7 @@ private async void IedConfigureSignals_Click(object sender, RoutedEventArgs e)
     private async void CommandPanel_Expanded(object sender, RoutedEventArgs e)
     {
         if (SelectedDevice != null)
-            await RefreshControlValuesAsync(SelectedDevice);
+            await RefreshControlValuesAsync(SelectedDevice, force: true);
     }
 
     private async void RefreshCommandValues_Click(object sender, RoutedEventArgs e)
@@ -800,12 +800,18 @@ private async Task ExecuteQuickControlAsync(SignalDefinition signal, string requ
           return;
   }
 
-  if (signal.ControlModelText == "Auto-detect" || signal.ControlCurrentValue == "-")
+  var capabilities = await _runtime.InspectControlAsync(device.DeviceId, signal, _applicationCancellation.Token);
+  signal.ControlCurrentValue = capabilities.CurrentValue;
+  device.RefreshCommandSignalProjection();
+  RebuildControlFeedbackIndex(device);
+  if (!capabilities.SupportsOperate)
+      throw new InvalidOperationException($"{signal.ObjectReference} is not command-ready: {capabilities.ControlModelText}.");
+  if (!CommandTestMode && SameControlState(signal, requestedValue, capabilities.CurrentValue))
   {
-      var capabilities = await _runtime.InspectControlAsync(device.DeviceId, signal, _applicationCancellation.Token);
-      signal.ControlCurrentValue = capabilities.CurrentValue;
-      device.RefreshCommandSignalProjection();
-      RebuildControlFeedbackIndex(device);
+      var current = string.IsNullOrWhiteSpace(capabilities.CurrentValue) ? "the requested state" : capabilities.CurrentValue;
+      signal.ControlLastResult = $"Already {current} — no command was sent.";
+      SetStatus($"{device.Name}: {signal.Name} is already {current}; duplicate control suppressed.");
+      return;
   }
 
   var result = await _runtime.ExecuteControlAsync(
@@ -848,6 +854,13 @@ private async Task ExecuteQuickControlAsync(SignalDefinition signal, string requ
         }
     }
 
+    private static bool SameControlState(SignalDefinition signal, string requested, string current)
+    {
+        if (signal.IsPositionControl && Iec61850ValueFormatter.TryNormalizeDbpos(requested, out var requestCode) && Iec61850ValueFormatter.TryNormalizeDbpos(current, out var currentCode)) return requestCode == currentCode;
+        if (signal.IsBooleanControl && bool.TryParse(requested, out var requestBool) && bool.TryParse(current, out var currentBool)) return requestBool == currentBool;
+        return requested.Trim().Equals(current.Trim(), StringComparison.OrdinalIgnoreCase);
+    }
+
     private static string BuildQuickControlResult(Iec61850ControlCommandResult result)
     {
         var timing = new List<string>();
diff --git a/Services/Iec61850MonitorRuntime.cs b/Services/Iec61850MonitorRuntime.cs
index 79679b7d..e36e627f 100644
--- a/Services/Iec61850MonitorRuntime.cs
+++ b/Services/Iec61850MonitorRuntime.cs
@@ -65,6 +65,10 @@ private sealed class DeviceSession
         public DateTime ReportSetupDeadlineUtc { get; set; } = DateTime.MinValue;
         public DateTime NextReconnectUtc { get; set; } = DateTime.MinValue;
         public int ConsecutiveSessionErrors { get; set; }
+        public DateTime LastSuccessfulIoUtc { get; set; } = DateTime.UtcNow;
+        public DateTime NextHealthProbeUtc { get; set; } = DateTime.MinValue;
+        public int ConsecutiveHealthProbeFailures { get; set; }
+        public string HealthProbePointKey { get; set; } = string.Empty;
     }
 
     private readonly ConcurrentDictionary<string, DeviceSession> _sessions = new(StringComparer.OrdinalIgnoreCase);
@@ -357,6 +361,10 @@ public async Task<IReadOnlyList<Iec61850MonitorPoint>> StartMonitoringAsync(
         session.ReportSetupNotBeforeUtc = DateTime.MinValue;
         session.ReportSetupDeadlineUtc = DateTime.MinValue;
         session.ConsecutiveSessionErrors = 0;
+        session.LastSuccessfulIoUtc = DateTime.UtcNow;
+        session.NextHealthProbeUtc = DateTime.UtcNow.AddSeconds(1);
+        session.ConsecutiveHealthProbeFailures = 0;
+        session.HealthProbePointKey = string.Empty;
 
         var safePollMs = Math.Clamp(pollingIntervalMs <= 0 ? 1000 : pollingIntervalMs, 50, 600000);
         foreach (var signal in selected)
@@ -372,6 +380,12 @@ public async Task<IReadOnlyList<Iec61850MonitorPoint>> StartMonitoringAsync(
             };
         }
 
+        session.HealthProbePointKey = session.Points.Values
+            .OrderByDescending(IsFastPoint)
+            .ThenBy(point => point.SignalName, StringComparer.OrdinalIgnoreCase)
+            .Select(point => point.PointKey)
+            .FirstOrDefault() ?? string.Empty;
+
         var plans = Iec61850ReportPlanner.BuildPlans(device, session.Points.Values);
         session.PendingReportPlans = plans;
         session.ReportSetupPending = plans.Count > 0;
@@ -604,15 +618,16 @@ private async Task MonitorLoopAsync(DeviceSession session, CancellationToken can
             {
                 if (!session.Client.IsConnected)
                 {
+                    MarkSessionOffline(session, "IEC 61850 transport is offline; smart reconnect is pending.");
                     await TryReconnectAsync(session, cancellationToken).ConfigureAwait(false);
-                    await Task.Delay(250, cancellationToken).ConfigureAwait(false);
+                    await Task.Delay(200, cancellationToken).ConfigureAwait(false);
                     continue;
                 }
 
                 await ReceiveReportSlicesAsync(session, cancellationToken).ConfigureAwait(false);
                 await PollDuePointsAsync(session, cancellationToken).ConfigureAwait(false);
+                await ProbeSessionHealthAsync(session, cancellationToken).ConfigureAwait(false);
                 await TryStartPendingReportSetupAsync(session, cancellationToken).ConfigureAwait(false);
-                session.ConsecutiveSessionErrors = 0;
 
                 await Task.Delay(CalculateLoopDelayMs(session), cancellationToken).ConfigureAwait(false);
             }
@@ -626,8 +641,8 @@ private async Task MonitorLoopAsync(DeviceSession session, CancellationToken can
                 Log("WARN", session.Device.Name,
                     $"Monitor loop recovered from {ex.GetType().Name}: {ex.Message}");
 
-                if (session.ConsecutiveSessionErrors >= 5)
-                    await ForceReconnectAsync(session).ConfigureAwait(false);
+                if (session.ConsecutiveSessionErrors >= 2)
+                    await ForceReconnectAsync(session, "Repeated monitor I/O failures.").ConfigureAwait(false);
 
                 try
                 {
@@ -684,8 +699,8 @@ private void UpdateDeviceAcquisitionSummary(DeviceSession session)
                 ? $"Smart reporting • static {staticReportCount} • fallback {pollingFallbackCount}"
                 : $"MMS polling fallback • {pollingFallbackCount} point(s)";
         session.Device.Detail = session.ActiveReportPlans.Count > 0
-            ? $"{session.Points.Count} point(s): live values started by MMS, then report-first acquisition was armed; MMS remains for q/t and low-rate verification."
-            : $"{session.Points.Count} point(s): reporting could not be armed; MMS polling fallback remains active.";
+            ? $"{session.Points.Count} point(s): event-driven reporting is primary; one lightweight MMS heartbeat and low-rate verification keep connection health reliable."
+            : $"{session.Points.Count} point(s): reporting could not be armed; bounded MMS polling fallback remains active.";
         session.Device.RefreshComputed();
 
         Log("INFO", session.Device.Name,
@@ -694,14 +709,14 @@ private void UpdateDeviceAcquisitionSummary(DeviceSession session)
 
     private static int CalculateLoopDelayMs(DeviceSession session)
     {
-        var defaultDelay = session.ActiveReportPlans.Count > 0 ? 5 : 10;
+        var defaultDelay = session.ActiveReportPlans.Count > 0 ? 12 : 25;
         if (!session.PollQueue.TryPeek(out _, out var dueTicks))
             return defaultDelay;
 
         var remainingMs = TimeSpan.FromTicks(Math.Max(0, dueTicks - DateTime.UtcNow.Ticks)).TotalMilliseconds;
         if (remainingMs <= 0)
-            return 1;
-        return Math.Clamp((int)Math.Ceiling(remainingMs), 1, defaultDelay);
+            return 2;
+        return Math.Clamp((int)Math.Ceiling(remainingMs), 2, defaultDelay);
     }
 
     private async Task ReceiveReportSlicesAsync(DeviceSession session, CancellationToken cancellationToken)
@@ -712,7 +727,7 @@ private async Task ReceiveReportSlicesAsync(DeviceSession session, CancellationT
 
         // Avoid N × blocking slices when an IED exposes many RCBs. A bounded
         // round-robin drain keeps reporting responsive without starving polling.
-        var batchCount = Math.Min(plans.Count, 8);
+        var batchCount = Math.Min(plans.Count, 4);
         for (var offset = 0; offset < batchCount; offset++)
         {
             cancellationToken.ThrowIfCancellationRequested();
@@ -720,10 +735,12 @@ private async Task ReceiveReportSlicesAsync(DeviceSession session, CancellationT
             var plan = plans[index];
             var slice = await session.Client.ReceiveReportMonitorSliceAsync(
                 plan.PlanId,
-                TimeSpan.FromMilliseconds(4),
+                TimeSpan.FromMilliseconds(3),
                 cancellationToken).ConfigureAwait(false);
 
             ProcessReportHealth(session, plan, slice);
+            if (slice.ReportFrames.Count > 0 || slice.Updates.Count > 0)
+                RecordSuccessfulIo(session);
 
             foreach (var update in slice.Updates)
             {
@@ -925,7 +942,7 @@ private static string ReportName(string actualReference, string plannedReference
     private async Task PollDuePointsAsync(DeviceSession session, CancellationToken cancellationToken)
     {
         var processed = 0;
-        while (processed < 12 && session.PollQueue.TryPeek(out var pointKey, out var dueTicks))
+        while (processed < 8 && session.PollQueue.TryPeek(out var pointKey, out var dueTicks))
         {
             var nowUtc = DateTime.UtcNow;
             if (dueTicks > nowUtc.Ticks)
@@ -968,6 +985,7 @@ private async Task PollDuePointsAsync(DeviceSession session, CancellationToken c
                 }
 
                 state.ConsecutiveErrors = 0;
+                RecordSuccessfulIo(session);
                 if (resolved.UsedAlternateReference(point.IecReference))
                 {
                     Log("INFO", session.Device.Name,
@@ -1057,7 +1075,7 @@ private async Task PollDuePointsAsync(DeviceSession session, CancellationToken c
             {
                 state.ConsecutiveErrors++;
                 EmitStatusSnapshot(point, state, $"Read error: {ex.Message}", "Bad / communication error");
-                if (state.ConsecutiveErrors >= 5)
+                if (state.ConsecutiveErrors >= 2)
                     session.ConsecutiveSessionErrors++;
             }
         }
@@ -1171,33 +1189,29 @@ private void EmitStatusSnapshot(
 
     private async Task TryReconnectAsync(DeviceSession session, CancellationToken cancellationToken)
     {
-        if (DateTime.UtcNow < session.NextReconnectUtc)
-            return;
-
-        session.NextReconnectUtc = DateTime.UtcNow.AddSeconds(3);
+        if (DateTime.UtcNow < session.NextReconnectUtc) return;
+        session.NextReconnectUtc = DateTime.UtcNow.AddSeconds(2);
+        MarkSessionOffline(session, $"Reconnecting MMS association to {session.Device.EndpointText}.");
         session.Device.Status = "Reconnecting";
-        session.Device.Detail = $"Retrying MMS association to {session.Device.EndpointText}.";
         Log("WARN", session.Device.Name, "IEC 61850 session is offline. Smart reconnect started.");
-
-        try
-        {
-            await session.Client.DisposeAsync().ConfigureAwait(false);
-        }
-        catch
+        try { await session.Client.DisposeAsync().ConfigureAwait(false); } catch { }
+        session.Client = new NativeIec61850Client();
+        try { await session.Client.ConnectAsync(session.Device.IpAddress, session.Device.Port, cancellationToken).ConfigureAwait(false); }
+        catch (OperationCanceledException) { throw; }
+        catch (Exception ex)
         {
-            // Old session cleanup must not block reconnect.
+            session.Device.Status = "Reconnect pending";
+            session.Device.Detail = ex.Message;
+            session.Device.RefreshComputed();
+            return;
         }
-
-        session.Client = new NativeIec61850Client();
-        await session.Client.ConnectAsync(session.Device.IpAddress, session.Device.Port, cancellationToken).ConfigureAwait(false);
         if (!session.Client.IsConnected)
         {
-            session.Device.IsConnected = false;
             session.Device.Status = "Reconnect pending";
             session.Device.Detail = session.Client.LastErrorMessage;
+            session.Device.RefreshComputed();
             return;
         }
-
         session.ActiveReportPlans.Clear();
         session.ActiveReportPlanOrder.Clear();
         session.PointPlanIds.Clear();
@@ -1207,26 +1221,71 @@ private async Task TryReconnectAsync(DeviceSession session, CancellationToken ca
         await StartReportPlansAsync(session, plans, cancellationToken).ConfigureAwait(false);
         ResetPollQueue(session);
         UpdateDeviceAcquisitionSummary(session);
-
         session.ConsecutiveSessionErrors = 0;
+        session.ConsecutiveHealthProbeFailures = 0;
+        session.LastSuccessfulIoUtc = DateTime.UtcNow;
+        session.NextHealthProbeUtc = DateTime.UtcNow.AddSeconds(1);
         session.Device.IsConnected = true;
         session.Device.Status = "Monitoring";
         session.Device.Detail = $"MMS reconnected. {session.Points.Count} point(s) resumed.";
+        session.Device.RefreshComputed();
         Log("INFO", session.Device.Name, "MMS reconnect successful. Monitoring resumed automatically.");
     }
 
-    private async Task ForceReconnectAsync(DeviceSession session)
+    private async Task ForceReconnectAsync(DeviceSession session, string reason)
     {
+        MarkSessionOffline(session, reason);
         session.ConsecutiveSessionErrors = 0;
+        session.ConsecutiveHealthProbeFailures = 0;
         session.NextReconnectUtc = DateTime.MinValue;
-        try
+        try { await session.Client.DisposeAsync().ConfigureAwait(false); } catch { }
+    }
+
+    private void RecordSuccessfulIo(DeviceSession session)
+    {
+        session.LastSuccessfulIoUtc = DateTime.UtcNow;
+        session.ConsecutiveHealthProbeFailures = 0;
+        session.ConsecutiveSessionErrors = 0;
+    }
+
+    private void MarkSessionOffline(DeviceSession session, string detail)
+    {
+        var wasConnected = session.Device.IsConnected;
+        session.Device.IsConnected = false;
+        session.Device.Status = "Offline";
+        session.Device.Detail = detail;
+        session.Device.AcquisitionMode = "Connection lost • reconnect pending";
+        session.Device.RefreshComputed();
+        if (wasConnected) Log("WARN", session.Device.Name, detail);
+    }
+
+    private async Task ProbeSessionHealthAsync(DeviceSession session, CancellationToken cancellationToken)
+    {
+        var now = DateTime.UtcNow;
+        if (now < session.NextHealthProbeUtc || now - session.LastSuccessfulIoUtc < TimeSpan.FromMilliseconds(900)) return;
+        session.NextHealthProbeUtc = now.AddSeconds(1);
+        if (string.IsNullOrWhiteSpace(session.HealthProbePointKey) || !session.Points.TryGetValue(session.HealthProbePointKey, out var point))
         {
-            await session.Client.DisposeAsync().ConfigureAwait(false);
+            point = session.Points.Values.FirstOrDefault();
+            if (point == null) return;
+            session.HealthProbePointKey = point.PointKey;
         }
-        catch
+        using var timeout = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
+        timeout.CancelAfter(TimeSpan.FromMilliseconds(900));
+        try
         {
-            // Reconnect loop will create a fresh client.
+            var signal = new SignalDefinition { Name = point.SignalName, ObjectReference = point.IecReference, FunctionalConstraint = point.FunctionalConstraint, DataType = point.IecDataType, Category = point.Category, Unit = point.Unit };
+            if (await IecSignalReadResolver.ReadAsync(session.Client, signal, timeout.Token).ConfigureAwait(false) != null)
+            {
+                RecordSuccessfulIo(session);
+                return;
+            }
         }
+        catch (OperationCanceledException) when (!cancellationToken.IsCancellationRequested) { }
+        catch (Exception ex) when (ex is not OperationCanceledException) { Log("WARN", session.Device.Name, $"MMS health probe failed: {ex.Message}"); }
+        session.ConsecutiveHealthProbeFailures++;
+        if (session.ConsecutiveHealthProbeFailures >= 2)
+            await ForceReconnectAsync(session, "IED stopped responding to two consecutive MMS health probes.").ConfigureAwait(false);
     }
 
     private static async Task<(string Quality, string DeviceTimestamp)> ReadCompanionAttributesAsync(
@@ -1530,14 +1589,14 @@ private static int GetVerificationPollIntervalMs(
         RuntimePointState state,
         bool reportAssigned)
     {
-        if (!reportAssigned || !state.ReportChangeVerified)
-            return point.PollingIntervalMs;
-
-        // Once an actual dchg/qchg/dupd edge is observed, report is primary. Keep a
-        // lightweight safety read so a misconfigured or later-stalled RCB cannot freeze
-        // the tester silently. Fast status points are validated more often than analogs.
-        var minimum = IsFastPoint(point) ? 5000 : 15000;
-        return Math.Clamp(Math.Max(point.PollingIntervalMs * 10, minimum), minimum, 60000);
+        if (!reportAssigned) return point.PollingIntervalMs;
+        if (state.ReportTrafficSeen)
+        {
+            var minimum = state.ReportChangeVerified ? (IsFastPoint(point) ? 10000 : 30000) : (IsFastPoint(point) ? 5000 : 15000);
+            return Math.Clamp(Math.Max(point.PollingIntervalMs * 15, minimum), minimum, 60000);
+        }
+        var awaitingReportMinimum = IsFastPoint(point) ? 2000 : 5000;
+        return Math.Clamp(Math.Max(point.PollingIntervalMs * 3, awaitingReportMinimum), awaitingReportMinimum, 15000);
     }
 
     private static string BuildPlanAcquisitionLabel(ReportControlPlan plan, bool dynamicDataSet)
diff --git a/docs/command-health-event-first-field-test.md b/docs/command-health-event-first-field-test.md
new file mode 100644
index 00000000..fd0d2bee
--- /dev/null
+++ b/docs/command-health-event-first-field-test.md
@@ -0,0 +1,11 @@
+# Command, liveness, and event-first field test
+
+Validate this follow-up with the IED connected and reporting active:
+
+1. When the breaker is Open, the Open button is disabled and clicking through stale UI state must produce no duplicate SBOw/Operate sequence.
+2. A valid Close followed by Open must each issue exactly one command sequence and reach positive CommandTermination/process feedback.
+3. Power off or unplug the IED. The relay icon should turn red after two bounded MMS health-probe failures (normally about two seconds), while smart reconnect remains active.
+4. Restore the IED. The app should reconnect, re-arm report acquisition, and return the icon to green.
+5. Confirm report-covered values show report acquisition as primary; per-point MMS reads should be low-rate verification rather than continuous primary polling.
+6. Confirm the Visual Studio Output window no longer floods `IsRecentlyChanged` binding errors for `SignalDefinition` rows.
+7. With Test enabled, the active-state command remains available so test controls are not suppressed by the process-state guard.