Index: MsgDefs.h
===================================================================
diff -u -r83a14225bb8fb696852284e9888c2ceb3f9c7e84 -ra97a0b47cc7b523936115483d21307715c41e3e4
--- MsgDefs.h	(.../MsgDefs.h)	(revision 83a14225bb8fb696852284e9888c2ceb3f9c7e84)
+++ MsgDefs.h	(.../MsgDefs.h)	(revision a97a0b47cc7b523936115483d21307715c41e3e4)
@@ -8,8 +8,8 @@
 *
 * @file    MsgDefs.h
 *
-* @author  (last)      Praneeth Bunne
-* @date    (last)      04-Jun-2026
+* @author  (last)      Michael Garthwaite
+* @date    (last)      11-Jun-2026
 *
 * @author  (original)  Sean Nash
 * @date    (original)  01-Aug-2024
@@ -210,6 +210,7 @@
     MSG_ID_TD_HEPARIN_PAUSE_RESUME_RESPONSE= 0xB2,                                  ///< TD response to pause/resume Heparin delivery request
     MSG_ID_FFU_SIGNAL_TD_UPDATE_AVAILABLE = 0xB3,                                   ///< FFU signal TD update is available.
     MSG_ID_FFU_SIGNAL_DD_UPDATE_AVAILABLE = 0xB4,                                   ///< FFU signal DD update is available.
+    MSG_ID_DD_SUBSTITUTION_PUMP_DATA = 0xB5,                                        ///< DD substitution pump broadcast data.
     MSG_ID_UI_VITALS_ADJUSTMENT_REQUEST = 0xB8,                                     ///< UI vitals adjustment request
     MSG_ID_TD_VITALS_ADJUSTMENT_RESPONSE  = 0xB9,                                   ///< TD vitals adjustment response
 
@@ -411,6 +412,9 @@
     MSG_ID_DD_BICART_UPPER_PRESSURE_OVERRIDE_REQUEST = 0xA06A,                          ///< DD bicarb cartridge upper threshold pressure override
     MSG_ID_DD_BICART_LOWER_PRESSURE_OVERRIDE_REQUEST = 0xA06B,                          ///< DD bicarb cartridge lower threshold pressure override
     MSG_ID_DD_FLOATER_LEVEL_OVERRIDE_REQUEST = 0xA06C,                                  ///< DD override request for D6 floater level override
+    MSG_ID_DD_SUBSTITUTION_PUMP_START_STOP_OVERRIDE_REQUEST = 0xA06D,                   ///< DD substitution pump start stop override request
+    MSG_ID_DD_SUBSTITUTION_PUMP_BROADCAST_INTERVAL_OVERRIDE_REQUEST = 0xA06E,           ///< DD substitution pump broadcast override request
+    MSG_ID_DD_SUBSTITUTION_PUMP_TARGET_RATE_OVERRIDE_REQUEST = 0xA06F,                  ///< DD substitution pump target speed override request.
 
     MSG_ID_FIRST_FP_TESTER_MESSAGE = 0xB000,                                            ///< First FP test message ID
     MSG_ID_FP_TESTER_LOGIN_REQUEST = MSG_ID_FIRST_FP_TESTER_MESSAGE,                    ///< FP tester log-in