Index: firmware/App/Services/Reservoirs.c
===================================================================
diff -u -rb607a94701f5844f2e850783239d1cb2df87fcd5 -r09cde48e11d32be58fe9e1e7c88ada33cff664f5
--- firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision b607a94701f5844f2e850783239d1cb2df87fcd5)
+++ firmware/App/Services/Reservoirs.c	(.../Reservoirs.c)	(revision 09cde48e11d32be58fe9e1e7c88ada33cff664f5)
@@ -499,8 +499,12 @@
  *************************************************************************/
 void setHDOperationMode( U32 mode, U32 subMode )
 {
+    // thread protection for queue operations
+    _disable_IRQ();
     hdModes.hdMode    = (HD_OP_MODE_T)mode;
     hdModes.hdSubMode = subMode;
+    // release thread protection
+    _enable_IRQ();
 }
 
 /*********************************************************************//**
@@ -514,7 +518,8 @@
  *************************************************************************/
 void getHDOperationMode( HD_MODE_SUB_MODE_T* mode )
 {
-    memcpy( mode, &hdModes, sizeof( HD_MODE_SUB_MODE_T ) );
+    mode->hdMode    = hdModes.hdMode;
+    mode->hdSubMode = hdModes.hdSubMode;
 }
 
 /*********************************************************************//**
Index: firmware/App/Services/SystemComm.c
===================================================================
diff -u -r821d1609f976b1fc01389f2e865aebcaa6434a78 -r09cde48e11d32be58fe9e1e7c88ada33cff664f5
--- firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision 821d1609f976b1fc01389f2e865aebcaa6434a78)
+++ firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision 09cde48e11d32be58fe9e1e7c88ada33cff664f5)
@@ -7,8 +7,8 @@
 *
 * @file    SystemComm.c
 *
-* @author  (last)      Dara Navaei
-* @date    (last)      11-Jun-2023
+* @author  (last)      Michael Garthwaite
+* @date    (last)      21-Aug-2023
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  05-Nov-2019
@@ -106,6 +106,7 @@
 static U32 canXmitRetryCtr = 0;                                             ///< counter for CAN transmit retries.
 static OVERRIDE_U32_T hdCommunicationStatus = {0, 0, 0, 0};                 ///< has HD sent a message since last check
 static volatile U32 timeOfLastHDCheckIn = 0;                                ///< last time we received an HD broadcast
+static OVERRIDE_U32_T pendingACKOverride = { 0, 0, 0, 0 };                  ///< Pending ACK override data structure.
 
 // ********** private function prototypes **********
 
@@ -781,7 +782,7 @@
     {
         for ( i = 0; i < PENDING_ACK_LIST_SIZE; i++ )
         {   // pending ACK expired?
-            if ( ( TRUE == pendingAckList[ i ].used ) && ( TRUE == didTimeout( pendingAckList[ i ].timeStamp, MSG_NOT_ACKED_TIMEOUT_MS ) ) )
+            if ( ( TRUE == pendingAckList[ i ].used ) && ( ( TRUE == didTimeout( pendingAckList[ i ].timeStamp, MSG_NOT_ACKED_TIMEOUT_MS ) ) ||  ( getU32OverrideValue( &pendingACKOverride ) > 0 ) ) )
             {   // if retries left, reset and resend pending message. Do not retry when in POST since the UI might not still be responsive
                 if ( pendingAckList[ i ].retries > 0 )
                 {
@@ -1029,7 +1030,7 @@
                 handleTestValveStateOverrideRequest( message );
                 break;
 
-            case MSG_ID_VALVES_STATES_PUBLISH_INTERVAL_OVERRIDE:
+            case MSG_ID_DG_VALVES_STATES_PUBLISH_INTERVAL_OVERRIDE:
                 handleTestValvesStatesPublishIntervalOverrideRequest( message );
                 break;
 
@@ -1357,6 +1358,26 @@
                 handleTestDGSetRecoverFromFaultModeSignal( message );
                 break;
 
+            case MSG_ID_DG_DRAIN_MODE_BROADCAST_INTERVAL_OVERRIDE:
+                handleTestDGDrainModeBroadcastOverrideRequest( message );
+                break;
+
+            case MSG_ID_DG_DIALIN_RO_ONLY_MODE_STATUS_REQUEST:
+                handleDGROStatusRequest( message );
+                break;
+
+            case MSG_ID_DG_RAM_STATUS_OVERRIDE:
+                handleTestDGRAMStatusOverrideRequest( message );
+                break;
+
+            case MSG_ID_DG_RESERVOIR_BROADCAST_INTERVAL_OVERRIDE:
+                handleTestDGReservoirOverrideRequest( message );
+                break;
+
+            case MSG_ID_DG_CAN_RECEIVE_ACK_MESSAGE_OVERRIDE:
+                handleTestDGPendingACKOverrideRequest( message );
+                break;
+
             default:
                 // TODO - unrecognized message ID received - ignore
                 break;
@@ -1414,4 +1435,48 @@
     return result;
 }
 
+/*********************************************************************//**
+ * @brief
+ * The testSetPendingACKOverride function overrides the
+ * pendingACKOverride variable.
+ * @details Inputs: none
+ * @details Outputs: pendingACKOverride
+ * @param value override for pendingACKOverride
+ * @return TRUE if override successful, FALSE if not
+ *************************************************************************/
+BOOL testSetPendingACKOverride( U32 value )
+{
+    BOOL result = FALSE;
+
+    if ( TRUE == isTestingActivated() )
+    {
+        result = TRUE;
+        pendingACKOverride.ovData = value;
+        pendingACKOverride.override = OVERRIDE_KEY;
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The testResetPendingACKOverride function resets the override
+ * of the pendingACKOverride variable.
+ * @details Inputs: none
+ * @details Outputs: pendingACKOverride
+ * @return TRUE if override reset successful, FALSE if not
+ *************************************************************************/
+BOOL testResetPendingACKOverride( void )
+{
+    BOOL result = FALSE;
+
+    if ( TRUE == isTestingActivated() )
+    {
+        result = TRUE;
+        pendingACKOverride.override = OVERRIDE_RESET;
+        pendingACKOverride.ovData = pendingACKOverride.ovInitData;
+    }
+
+    return result;
+}
 /**@}*/
Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -rb607a94701f5844f2e850783239d1cb2df87fcd5 -r09cde48e11d32be58fe9e1e7c88ada33cff664f5
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision b607a94701f5844f2e850783239d1cb2df87fcd5)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 09cde48e11d32be58fe9e1e7c88ada33cff664f5)
@@ -341,7 +341,7 @@
     // create a message record
     blankMessage( &msg );
     msg.hdr.msgID = MSG_ID_ALARM_TRIGGERED;
-    msg.hdr.payloadLen = sizeof( U32 ) * 5;
+    msg.hdr.payloadLen = sizeof( U32 ) * 8;
 
     memcpy( payloadPtr, &alarm, sizeof( U32 ) );
     payloadPtr += sizeof( U32 );
@@ -1551,9 +1551,9 @@
         U32 mode    = 0;
         U32 subMode = 0;
 
-        memcpy( payloadPtr, &mode, sizeof( U32 ) );
+        memcpy( &mode, payloadPtr, sizeof( U32 ) );
         payloadPtr += sizeof( U32 );
-        memcpy( payloadPtr, &subMode, sizeof( U32 ) );
+        memcpy( &subMode, payloadPtr, sizeof( U32 ) );
 
         setHDOperationMode( mode, subMode );
         status = TRUE;