diff --git a/modules/cfe_testcase/src/sb_sendrecv_test.c b/modules/cfe_testcase/src/sb_sendrecv_test.c
index 81909d0e5..4f8be7ac2 100644
--- a/modules/cfe_testcase/src/sb_sendrecv_test.c
+++ b/modules/cfe_testcase/src/sb_sendrecv_test.c
@@ -145,8 +145,9 @@ void TestBasicTransmitRecv(void)
     UtAssert_INT32_EQ(CFE_SB_ReceiveBuffer(&MsgBuf, PipeId1, -100), CFE_SB_BAD_ARGUMENT);
 
     /*
-     * Note, the CFE_SB_TransmitMsg ignores the "IncrementSequence" flag for commands.
-     * Thus, all the sequence numbers should come back with the original value set (11)
+     * Note, the CFE_SB_TransmitMsg now adheres to the "UpdateHeader" flag.
+     * Thus, the sequence numbers should come back with the value from the Route (1-2)
+     * rather than the value the message was filled with initially.
      *
      * Note this also utilizes the CFE_SB_PEND_FOREVER flag - if working correctly,
      * there should be a message in the queue, so it should not block.
@@ -157,7 +158,7 @@ void TestBasicTransmitRecv(void)
     CFE_Assert_MSGID_EQ(MsgId, CFE_FT_CMD_MSGID);
     CmdPtr = (const CFE_FT_TestCmdMessage_t *)MsgBuf;
     UtAssert_UINT32_EQ(CmdPtr->CmdPayload, 0x0c0ffee);
-    UtAssert_UINT32_EQ(Seq1, 11);
+    UtAssert_UINT32_EQ(Seq1, 1);
 
     UtAssert_INT32_EQ(CFE_SB_ReceiveBuffer(&MsgBuf, PipeId1, CFE_SB_PEND_FOREVER), CFE_SUCCESS);
     UtAssert_INT32_EQ(CFE_MSG_GetMsgId(&MsgBuf->Msg, &MsgId), CFE_SUCCESS);
@@ -165,7 +166,7 @@ void TestBasicTransmitRecv(void)
     CFE_Assert_MSGID_EQ(MsgId, CFE_FT_CMD_MSGID);
     CmdPtr = (const CFE_FT_TestCmdMessage_t *)MsgBuf;
     UtAssert_UINT32_EQ(CmdPtr->CmdPayload, 0x1c0ffee);
-    UtAssert_UINT32_EQ(Seq1, 11);
+    UtAssert_UINT32_EQ(Seq1, 2);
 
     UtAssert_INT32_EQ(CFE_SB_ReceiveBuffer(&MsgBuf, PipeId1, CFE_SB_PEND_FOREVER), CFE_SUCCESS);
     UtAssert_INT32_EQ(CFE_MSG_GetMsgId(&MsgBuf->Msg, &MsgId), CFE_SUCCESS);
@@ -480,7 +481,7 @@ void TestZeroCopyTransmitRecv(void)
     /* Receive and get initial sequence count */
     UtAssert_INT32_EQ(CFE_SB_ReceiveBuffer(&MsgBuf, PipeId1, CFE_SB_POLL), CFE_SUCCESS);
     UtAssert_INT32_EQ(CFE_MSG_GetSequenceCount(&MsgBuf->Msg, &SeqCmd1), CFE_SUCCESS);
-    UtAssert_UINT32_EQ(SeqCmd1, 1234); /* NOTE: commands currently do NOT honor "Increment" flag */
+    UtAssert_UINT32_EQ(SeqCmd1, 6); /* NOTE: commands now honor "Update" flag */
     UtAssert_INT32_EQ(CFE_SB_ReceiveBuffer(&MsgBuf, PipeId2, CFE_SB_POLL), CFE_SUCCESS);
     UtAssert_INT32_EQ(CFE_MSG_GetSequenceCount(&MsgBuf->Msg, &SeqTlm1), CFE_SUCCESS);
 
@@ -497,7 +498,7 @@ void TestZeroCopyTransmitRecv(void)
     /* Receive and get current sequence count */
     UtAssert_INT32_EQ(CFE_SB_ReceiveBuffer(&MsgBuf, PipeId1, CFE_SB_POLL), CFE_SUCCESS);
     UtAssert_INT32_EQ(CFE_MSG_GetSequenceCount(&MsgBuf->Msg, &SeqCmd2), CFE_SUCCESS);
-    UtAssert_UINT32_EQ(SeqCmd2, 1234); /* NOTE: commands currently do NOT honor "Increment" flag */
+    UtAssert_UINT32_EQ(SeqCmd2, 7); /* NOTE: commands now honor "Update" flag */
     UtAssert_INT32_EQ(CFE_SB_ReceiveBuffer(&MsgBuf, PipeId2, CFE_SB_POLL), CFE_SUCCESS);
     UtAssert_INT32_EQ(CFE_MSG_GetSequenceCount(&MsgBuf->Msg, &SeqTlm2), CFE_SUCCESS);
     UtAssert_UINT32_EQ(SeqTlm2, CFE_MSG_GetNextSequenceCount(SeqTlm1)); /* should be +1 from the previous */
diff --git a/modules/core_api/fsw/inc/cfe_msg.h b/modules/core_api/fsw/inc/cfe_msg.h
index ba91e77b8..96a92d10b 100644
--- a/modules/core_api/fsw/inc/cfe_msg.h
+++ b/modules/core_api/fsw/inc/cfe_msg.h
@@ -59,6 +59,31 @@
  * \retval #CFE_MSG_BAD_ARGUMENT    \copybrief CFE_MSG_BAD_ARGUMENT
  */
 CFE_Status_t CFE_MSG_Init(CFE_MSG_Message_t *MsgPtr, CFE_SB_MsgId_t MsgId, CFE_MSG_Size_t Size);
+
+/*****************************************************************************/
+/**
+ * \brief Set/compute all dynamically-updated headers on a message
+ *
+ * \par Description
+ *          This routine updates all dynamic header fields on a message, and is typically
+ *          invoked via SB just prior to broadcasting the message.  Dynamic headers include
+ *          are values that should be computed/updated per message, including:
+ *                  - the sequence number
+ *                  - the timestamp, if present
+ *                  - any error control or checksum fields, if present
+ *
+ *          The MSG module implementation determines which header fields meet this criteria
+ *          and how they should be computed.
+ *
+ * \param[inout] MsgPtr  A pointer to the buffer that contains the message @nonnull.
+ * \param[in]    SeqCnt  The current sequence number from the message route
+ *
+ * \return Execution status, see \ref CFEReturnCodes
+ * \retval #CFE_SUCCESS             \copybrief CFE_SUCCESS
+ * \retval #CFE_MSG_BAD_ARGUMENT    \copybrief CFE_MSG_BAD_ARGUMENT
+ */
+CFE_Status_t CFE_MSG_UpdateHeader(CFE_MSG_Message_t *MsgPtr, CFE_MSG_SequenceCount_t SeqCnt);
+
 /**\}*/
 
 /** \defgroup CFEAPIMSGHeaderPri cFE Message Primary Header APIs
diff --git a/modules/core_api/fsw/inc/cfe_sb.h b/modules/core_api/fsw/inc/cfe_sb.h
index 99973882b..a670d0120 100644
--- a/modules/core_api/fsw/inc/cfe_sb.h
+++ b/modules/core_api/fsw/inc/cfe_sb.h
@@ -402,18 +402,26 @@ CFE_Status_t CFE_SB_UnsubscribeLocal(CFE_SB_MsgId_t MsgId, CFE_SB_PipeId_t PipeI
 **          software bus will read the message ID from the message header to
 **          determine which pipes should receive the message.
 **
+**          In general, the "UpdateHeader" parameter should be passed as "true"
+**          if the message was newly constructed by the sender and is being sent
+**          for the first time.  When forwarding a message that originated from
+**          an external entity (e.g. messages passing through CI or SBN), the
+**          parameter should be passed as "false" to not overwrite existing data.
+**
 ** \par Assumptions, External Events, and Notes:
 **          - This routine will not normally wait for the receiver tasks to
 **            process the message before returning control to the caller's task.
 **          - However, if a higher priority task is pending and subscribed to
 **            this message, that task may get to run before returning
 **            control to the caller.
+**          - In previous versions of CFE, the boolean parameter referred to the
+**            sequence number header of telemetry messages only.  This has been
+**            extended to apply more generically to any headers, as determined by
+**            the CFE MSG implementation.
 **
 ** \param[in]  MsgPtr       A pointer to the message to be sent @nonnull.  This must point
 **                          to the first byte of the message header.
-** \param[in] IncrementSequenceCount Boolean to increment the internally tracked
-**                                   sequence count and update the message if the
-**                                   buffer contains a telemetry message
+** \param[in] UpdateHeader  Update the headers of the message
 **
 ** \return Execution status, see \ref CFEReturnCodes
 ** \retval #CFE_SUCCESS         \copybrief CFE_SUCCESS
@@ -421,7 +429,7 @@ CFE_Status_t CFE_SB_UnsubscribeLocal(CFE_SB_MsgId_t MsgId, CFE_SB_PipeId_t PipeI
 ** \retval #CFE_SB_MSG_TOO_BIG  \copybrief CFE_SB_MSG_TOO_BIG
 ** \retval #CFE_SB_BUF_ALOC_ERR \covtest \copybrief CFE_SB_BUF_ALOC_ERR
 **/
-CFE_Status_t CFE_SB_TransmitMsg(const CFE_MSG_Message_t *MsgPtr, bool IncrementSequenceCount);
+CFE_Status_t CFE_SB_TransmitMsg(const CFE_MSG_Message_t *MsgPtr, bool UpdateHeader);
 
 /*****************************************************************************/
 /**
@@ -536,6 +544,12 @@ CFE_Status_t CFE_SB_ReleaseMessageBuffer(CFE_SB_Buffer_t *BufPtr);
 **          internal buffer.  The "zero copy" interface can be used to improve
 **          performance in high-rate, high-volume software bus traffic.
 **
+**          In general, the "UpdateHeader" parameter should be passed as "true"
+**          if the message was newly constructed by the sender and is being sent
+**          for the first time.  When forwarding a message that originated from
+**          an external entity (e.g. messages passing through CI or SBN), the
+**          parameter should be passed as "false" to not overwrite existing data.
+**
 ** \par Assumptions, External Events, and Notes:
 **          -# A handle returned by #CFE_SB_AllocateMessageBuffer is "consumed" by
 **             a _successful_ call to #CFE_SB_TransmitBuffer.
@@ -553,17 +567,15 @@ CFE_Status_t CFE_SB_ReleaseMessageBuffer(CFE_SB_Buffer_t *BufPtr);
 **          -# This function will increment and apply the internally tracked
 **             sequence counter if set to do so.
 **
-** \param[in] BufPtr                 A pointer to the buffer to be sent @nonnull.
-** \param[in] IncrementSequenceCount Boolean to increment the internally tracked
-**                                   sequence count and update the message if the
-**                                   buffer contains a telemetry message
+** \param[in] BufPtr        A pointer to the buffer to be sent @nonnull.
+** \param[in] UpdateHeader  Update the headers of the message
 **
 ** \return Execution status, see \ref CFEReturnCodes
 ** \retval #CFE_SUCCESS         \copybrief CFE_SUCCESS
 ** \retval #CFE_SB_BAD_ARGUMENT \copybrief CFE_SB_BAD_ARGUMENT
 ** \retval #CFE_SB_MSG_TOO_BIG  \copybrief CFE_SB_MSG_TOO_BIG
 **/
-CFE_Status_t CFE_SB_TransmitBuffer(CFE_SB_Buffer_t *BufPtr, bool IncrementSequenceCount);
+CFE_Status_t CFE_SB_TransmitBuffer(CFE_SB_Buffer_t *BufPtr, bool UpdateHeader);
 
 /** @} */
 
diff --git a/modules/core_api/ut-stubs/src/cfe_config_stubs.c b/modules/core_api/ut-stubs/src/cfe_config_stubs.c
index 6a90f1b93..1ac7943a8 100644
--- a/modules/core_api/ut-stubs/src/cfe_config_stubs.c
+++ b/modules/core_api/ut-stubs/src/cfe_config_stubs.c
@@ -25,8 +25,8 @@
 #include "cfe_config.h"
 #include "utgenstub.h"
 
-extern void UT_DefaultHandler_CFE_Config_GetObjPointer(void *, UT_EntryKey_t, const UT_StubContext_t *);
-extern void UT_DefaultHandler_CFE_Config_GetString(void *, UT_EntryKey_t, const UT_StubContext_t *);
+void UT_DefaultHandler_CFE_Config_GetObjPointer(void *, UT_EntryKey_t, const UT_StubContext_t *);
+void UT_DefaultHandler_CFE_Config_GetString(void *, UT_EntryKey_t, const UT_StubContext_t *);
 
 /*
  * ----------------------------------------------------
diff --git a/modules/core_api/ut-stubs/src/cfe_error_stubs.c b/modules/core_api/ut-stubs/src/cfe_error_stubs.c
new file mode 100644
index 000000000..540769933
--- /dev/null
+++ b/modules/core_api/ut-stubs/src/cfe_error_stubs.c
@@ -0,0 +1,43 @@
+/************************************************************************
+ * NASA Docket No. GSC-18,719-1, and identified as “core Flight System: Bootes”
+ *
+ * Copyright (c) 2020 United States Government as represented by the
+ * Administrator of the National Aeronautics and Space Administration.
+ * All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License. You may obtain
+ * a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ ************************************************************************/
+
+/**
+ * @file
+ *
+ * Auto-Generated stub implementations for functions defined in cfe_error header
+ */
+
+#include "cfe_error.h"
+#include "utgenstub.h"
+
+/*
+ * ----------------------------------------------------
+ * Generated stub function for CFE_ES_StatusToString()
+ * ----------------------------------------------------
+ */
+char *CFE_ES_StatusToString(CFE_Status_t status, CFE_StatusString_t *status_string)
+{
+    UT_GenStub_SetupReturnBuffer(CFE_ES_StatusToString, char *);
+
+    UT_GenStub_AddParam(CFE_ES_StatusToString, CFE_Status_t, status);
+    UT_GenStub_AddParam(CFE_ES_StatusToString, CFE_StatusString_t *, status_string);
+
+    UT_GenStub_Execute(CFE_ES_StatusToString, Basic, NULL);
+
+    return UT_GenStub_GetReturnValue(CFE_ES_StatusToString, char *);
+}
diff --git a/modules/core_api/ut-stubs/src/cfe_es_stubs.c b/modules/core_api/ut-stubs/src/cfe_es_stubs.c
index 9dfdf261b..d990609ed 100644
--- a/modules/core_api/ut-stubs/src/cfe_es_stubs.c
+++ b/modules/core_api/ut-stubs/src/cfe_es_stubs.c
@@ -69,6 +69,7 @@ CFE_Status_t CFE_ES_AppID_ToIndex(CFE_ES_AppId_t AppID, uint32 *Idx)
  */
 void CFE_ES_BackgroundWakeup(void)
 {
+
     UT_GenStub_Execute(CFE_ES_BackgroundWakeup, Basic, NULL);
 }
 
@@ -216,6 +217,7 @@ void CFE_ES_ExitApp(uint32 ExitStatus)
  */
 void CFE_ES_ExitChildTask(void)
 {
+
     UT_GenStub_Execute(CFE_ES_ExitChildTask, Basic, NULL);
 }
 
@@ -602,6 +604,7 @@ CFE_Status_t CFE_ES_IncrementGenCounter(CFE_ES_CounterId_t CounterId)
  */
 void CFE_ES_IncrementTaskCounter(void)
 {
+
     UT_GenStub_Execute(CFE_ES_IncrementTaskCounter, Basic, NULL);
 }
 
@@ -731,6 +734,7 @@ int32 CFE_ES_PoolDelete(CFE_ES_MemHandle_t PoolID)
  */
 void CFE_ES_ProcessAsyncEvent(void)
 {
+
     UT_GenStub_Execute(CFE_ES_ProcessAsyncEvent, Basic, NULL);
 }
 
@@ -950,20 +954,3 @@ CFE_Status_t CFE_ES_WriteToSysLog(const char *SpecStringPtr, ...)
 
     return UT_GenStub_GetReturnValue(CFE_ES_WriteToSysLog, CFE_Status_t);
 }
-
-/*
- * ----------------------------------------------------
- * Generated stub function for CFE_ES_StatusToString()
- * ----------------------------------------------------
- */
-char *CFE_ES_StatusToString(CFE_Status_t status, CFE_StatusString_t *status_string)
-{
-    UT_GenStub_SetupReturnBuffer(CFE_ES_StatusToString, char *);
-
-    UT_GenStub_AddParam(CFE_ES_StatusToString, CFE_Status_t, status);
-    UT_GenStub_AddParam(CFE_ES_StatusToString, CFE_StatusString_t *, status_string);
-
-    UT_GenStub_Execute(CFE_ES_StatusToString, Basic, NULL);
-
-    return UT_GenStub_GetReturnValue(CFE_ES_StatusToString, char *);
-}
diff --git a/modules/core_api/ut-stubs/src/cfe_msg_stubs.c b/modules/core_api/ut-stubs/src/cfe_msg_stubs.c
index cf59efc6c..066f8e8d1 100644
--- a/modules/core_api/ut-stubs/src/cfe_msg_stubs.c
+++ b/modules/core_api/ut-stubs/src/cfe_msg_stubs.c
@@ -621,6 +621,23 @@ CFE_Status_t CFE_MSG_SetType(CFE_MSG_Message_t *MsgPtr, CFE_MSG_Type_t Type)
     return UT_GenStub_GetReturnValue(CFE_MSG_SetType, CFE_Status_t);
 }
 
+/*
+ * ----------------------------------------------------
+ * Generated stub function for CFE_MSG_UpdateHeader()
+ * ----------------------------------------------------
+ */
+CFE_Status_t CFE_MSG_UpdateHeader(CFE_MSG_Message_t *MsgPtr, CFE_MSG_SequenceCount_t SeqCnt)
+{
+    UT_GenStub_SetupReturnBuffer(CFE_MSG_UpdateHeader, CFE_Status_t);
+
+    UT_GenStub_AddParam(CFE_MSG_UpdateHeader, CFE_MSG_Message_t *, MsgPtr);
+    UT_GenStub_AddParam(CFE_MSG_UpdateHeader, CFE_MSG_SequenceCount_t, SeqCnt);
+
+    UT_GenStub_Execute(CFE_MSG_UpdateHeader, Basic, NULL);
+
+    return UT_GenStub_GetReturnValue(CFE_MSG_UpdateHeader, CFE_Status_t);
+}
+
 /*
  * ----------------------------------------------------
  * Generated stub function for CFE_MSG_ValidateChecksum()
diff --git a/modules/core_api/ut-stubs/src/cfe_sb_stubs.c b/modules/core_api/ut-stubs/src/cfe_sb_stubs.c
index f31ef71f8..3f541d54c 100644
--- a/modules/core_api/ut-stubs/src/cfe_sb_stubs.c
+++ b/modules/core_api/ut-stubs/src/cfe_sb_stubs.c
@@ -384,12 +384,12 @@ void CFE_SB_TimeStampMsg(CFE_MSG_Message_t *MsgPtr)
  * Generated stub function for CFE_SB_TransmitBuffer()
  * ----------------------------------------------------
  */
-CFE_Status_t CFE_SB_TransmitBuffer(CFE_SB_Buffer_t *BufPtr, bool IncrementSequenceCount)
+CFE_Status_t CFE_SB_TransmitBuffer(CFE_SB_Buffer_t *BufPtr, bool UpdateHeader)
 {
     UT_GenStub_SetupReturnBuffer(CFE_SB_TransmitBuffer, CFE_Status_t);
 
     UT_GenStub_AddParam(CFE_SB_TransmitBuffer, CFE_SB_Buffer_t *, BufPtr);
-    UT_GenStub_AddParam(CFE_SB_TransmitBuffer, bool, IncrementSequenceCount);
+    UT_GenStub_AddParam(CFE_SB_TransmitBuffer, bool, UpdateHeader);
 
     UT_GenStub_Execute(CFE_SB_TransmitBuffer, Basic, UT_DefaultHandler_CFE_SB_TransmitBuffer);
 
@@ -401,12 +401,12 @@ CFE_Status_t CFE_SB_TransmitBuffer(CFE_SB_Buffer_t *BufPtr, bool IncrementSequen
  * Generated stub function for CFE_SB_TransmitMsg()
  * ----------------------------------------------------
  */
-CFE_Status_t CFE_SB_TransmitMsg(const CFE_MSG_Message_t *MsgPtr, bool IncrementSequenceCount)
+CFE_Status_t CFE_SB_TransmitMsg(const CFE_MSG_Message_t *MsgPtr, bool UpdateHeader)
 {
     UT_GenStub_SetupReturnBuffer(CFE_SB_TransmitMsg, CFE_Status_t);
 
     UT_GenStub_AddParam(CFE_SB_TransmitMsg, const CFE_MSG_Message_t *, MsgPtr);
-    UT_GenStub_AddParam(CFE_SB_TransmitMsg, bool, IncrementSequenceCount);
+    UT_GenStub_AddParam(CFE_SB_TransmitMsg, bool, UpdateHeader);
 
     UT_GenStub_Execute(CFE_SB_TransmitMsg, Basic, UT_DefaultHandler_CFE_SB_TransmitMsg);
 
diff --git a/modules/core_api/ut-stubs/src/cfe_time_stubs.c b/modules/core_api/ut-stubs/src/cfe_time_stubs.c
index 40519dfb1..999f06008 100644
--- a/modules/core_api/ut-stubs/src/cfe_time_stubs.c
+++ b/modules/core_api/ut-stubs/src/cfe_time_stubs.c
@@ -113,6 +113,7 @@ void CFE_TIME_ExternalTime(CFE_TIME_SysTime_t NewTime)
  */
 void CFE_TIME_ExternalTone(void)
 {
+
     UT_GenStub_Execute(CFE_TIME_ExternalTone, Basic, NULL);
 }
 
@@ -263,6 +264,7 @@ CFE_TIME_SysTime_t CFE_TIME_GetUTC(void)
  */
 void CFE_TIME_Local1HzISR(void)
 {
+
     UT_GenStub_Execute(CFE_TIME_Local1HzISR, Basic, NULL);
 }
 
diff --git a/modules/msg/fsw/src/cfe_msg_init.c b/modules/msg/fsw/src/cfe_msg_init.c
index 3c29432a4..ab988f4bb 100644
--- a/modules/msg/fsw/src/cfe_msg_init.c
+++ b/modules/msg/fsw/src/cfe_msg_init.c
@@ -22,6 +22,7 @@
 #include "cfe_msg.h"
 #include "cfe_msg_priv.h"
 #include "cfe_msg_defaults.h"
+#include "cfe_time.h"
 #include "string.h"
 
 /*----------------------------------------------------------------
@@ -52,3 +53,34 @@ CFE_Status_t CFE_MSG_Init(CFE_MSG_Message_t *MsgPtr, CFE_SB_MsgId_t MsgId, CFE_M
 
     return status;
 }
+
+/*----------------------------------------------------------------
+ *
+ * Implemented per public API
+ * See description in header file for argument/return detail
+ *
+ *-----------------------------------------------------------------*/
+CFE_Status_t CFE_MSG_UpdateHeader(CFE_MSG_Message_t *MsgPtr, CFE_MSG_SequenceCount_t SeqCnt)
+{
+    if (MsgPtr == NULL)
+    {
+        return CFE_MSG_BAD_ARGUMENT;
+    }
+
+    /* Sequence count is in the basic CCSDS Primary Hdr, so all msgs have it */
+    CFE_MSG_SetSequenceCount(MsgPtr, SeqCnt);
+
+    /*
+     * TLM packets have a timestamp in the secondary header.
+     * This may fail if this is not a TLM packet (that is OK)
+     */
+    CFE_MSG_SetMsgTime(MsgPtr, CFE_TIME_GetTime());
+
+    /*
+     * CMD packets have a checksum in the secondary header.
+     * This may fail if this is not a CMD packet (that is OK)
+     */
+    CFE_MSG_GenerateChecksum(MsgPtr);
+
+    return CFE_SUCCESS;
+}
\ No newline at end of file
diff --git a/modules/msg/ut-coverage/msg_UT.c b/modules/msg/ut-coverage/msg_UT.c
index ea83b5f8c..e0bd532ff 100644
--- a/modules/msg/ut-coverage/msg_UT.c
+++ b/modules/msg/ut-coverage/msg_UT.c
@@ -43,6 +43,7 @@ void UtTest_Setup(void)
     UtPrintf("Message header coverage test...");
 
     UT_ADD_TEST(Test_MSG_Init);
+    UT_ADD_TEST(Test_MSG_UpdateHeader);
     Test_MSG_CCSDSPri();
     Test_MSG_CCSDSExt();
     Test_MSG_MsgId_Shared();
diff --git a/modules/msg/ut-coverage/test_cfe_msg_init.c b/modules/msg/ut-coverage/test_cfe_msg_init.c
index a072566ae..a707c3618 100644
--- a/modules/msg/ut-coverage/test_cfe_msg_init.c
+++ b/modules/msg/ut-coverage/test_cfe_msg_init.c
@@ -124,3 +124,40 @@ void Test_MSG_Init(void)
     UtAssert_UINT32_EQ(Test_MSG_Pri_NotZero(CFE_MSG_PTR(cmd)) & ~MSG_HDRVER_FLAG,
                        MSG_APID_FLAG | MSG_HASSEC_FLAG | MSG_TYPE_FLAG | MSG_LENGTH_FLAG | MSG_SEGMENT_FLAG);
 }
+
+/*
+ * Test MSG Update Header
+ */
+void Test_MSG_UpdateHeader(void)
+{
+    union
+    {
+        CFE_MSG_Message_t         msg;
+        CFE_MSG_CommandHeader_t   cmd;
+        CFE_MSG_TelemetryHeader_t tlm;
+
+    } LocalBuf;
+    CFE_MSG_SequenceCount_t SeqCnt;
+    CFE_MSG_SequenceCount_t CheckCnt;
+
+    memset(&LocalBuf, 0, sizeof(LocalBuf));
+    SeqCnt   = 1;
+    CheckCnt = 0;
+
+    /* bad buffer */
+    UtAssert_INT32_EQ(CFE_MSG_UpdateHeader(NULL, SeqCnt), CFE_MSG_BAD_ARGUMENT);
+
+    /* nominal, cmd */
+    CFE_MSG_SetType(&LocalBuf.msg, CFE_MSG_Type_Cmd);
+    CFE_UtAssert_SUCCESS(CFE_MSG_UpdateHeader(&LocalBuf.msg, SeqCnt));
+    CFE_MSG_GetSequenceCount(&LocalBuf.msg, &CheckCnt);
+    UtAssert_UINT32_EQ(CheckCnt, SeqCnt);
+    ++SeqCnt;
+
+    /* nominal, tlm */
+    CFE_MSG_SetType(&LocalBuf.msg, CFE_MSG_Type_Tlm);
+    CFE_UtAssert_SUCCESS(CFE_MSG_UpdateHeader(&LocalBuf.msg, SeqCnt));
+    CFE_MSG_GetSequenceCount(&LocalBuf.msg, &CheckCnt);
+    UtAssert_UINT32_EQ(CheckCnt, SeqCnt);
+    ++SeqCnt;
+}
diff --git a/modules/msg/ut-coverage/test_cfe_msg_init.h b/modules/msg/ut-coverage/test_cfe_msg_init.h
index a80362d03..3c5b25f62 100644
--- a/modules/msg/ut-coverage/test_cfe_msg_init.h
+++ b/modules/msg/ut-coverage/test_cfe_msg_init.h
@@ -33,5 +33,6 @@
  */
 /* Test extended header mission functionality */
 void Test_MSG_Init(void);
+void Test_MSG_UpdateHeader(void);
 
 #endif /* TEST_CFE_MSG_INIT_H */
diff --git a/modules/sb/fsw/src/cfe_sb_api.c b/modules/sb/fsw/src/cfe_sb_api.c
index 674c20cca..1b9574260 100644
--- a/modules/sb/fsw/src/cfe_sb_api.c
+++ b/modules/sb/fsw/src/cfe_sb_api.c
@@ -1287,7 +1287,7 @@ int32 CFE_SB_UnsubscribeFull(CFE_SB_MsgId_t MsgId, CFE_SB_PipeId_t PipeId, uint8
  * See description in header file for argument/return detail
  *
  *-----------------------------------------------------------------*/
-CFE_Status_t CFE_SB_TransmitMsg(const CFE_MSG_Message_t *MsgPtr, bool IncrementSequenceCount)
+CFE_Status_t CFE_SB_TransmitMsg(const CFE_MSG_Message_t *MsgPtr, bool UpdateHeader)
 {
     int32             Status;
     CFE_MSG_Size_t    Size  = 0;
@@ -1347,9 +1347,9 @@ CFE_Status_t CFE_SB_TransmitMsg(const CFE_MSG_Message_t *MsgPtr, bool IncrementS
     {
         /* Copy actual message content into buffer and set its metadata */
         memcpy(&BufDscPtr->Content, MsgPtr, Size);
-        BufDscPtr->MsgId        = MsgId;
-        BufDscPtr->ContentSize  = Size;
-        BufDscPtr->AutoSequence = IncrementSequenceCount;
+        BufDscPtr->MsgId       = MsgId;
+        BufDscPtr->ContentSize = Size;
+        BufDscPtr->NeedsUpdate = UpdateHeader;
         CFE_MSG_GetType(MsgPtr, &BufDscPtr->ContentType);
 
         /*
@@ -1551,13 +1551,15 @@ void CFE_SB_BroadcastBufferToRoute(CFE_SB_BufferD_t *BufDscPtr, CFE_SBR_RouteId_
     if (CFE_SBR_IsValidRouteId(RouteId))
     {
         /* Set the seq count if requested (while locked) before actually sending */
-        /* For some reason this is only done for TLM types (historical, TBD) */
-        if (BufDscPtr->AutoSequence && BufDscPtr->ContentType == CFE_MSG_Type_Tlm)
+        if (BufDscPtr->NeedsUpdate)
         {
             CFE_SBR_IncrementSequenceCounter(RouteId);
 
-            /* Write the sequence into the message header itself (overwrites whatever was there) */
-            CFE_MSG_SetSequenceCount(&BufDscPtr->Content.Msg, CFE_SBR_GetSequenceCounter(RouteId));
+            /* Update all MSG headers based on the current sequence */
+            CFE_MSG_UpdateHeader(&BufDscPtr->Content.Msg, CFE_SBR_GetSequenceCounter(RouteId));
+
+            /* Clear the flag, just in case */
+            BufDscPtr->NeedsUpdate = false;
         }
 
         /* Send the packet to all destinations  */
@@ -2116,7 +2118,7 @@ CFE_Status_t CFE_SB_ReleaseMessageBuffer(CFE_SB_Buffer_t *BufPtr)
  * See description in header file for argument/return detail
  *
  *-----------------------------------------------------------------*/
-CFE_Status_t CFE_SB_TransmitBuffer(CFE_SB_Buffer_t *BufPtr, bool IncrementSequenceCount)
+CFE_Status_t CFE_SB_TransmitBuffer(CFE_SB_Buffer_t *BufPtr, bool UpdateHeader)
 {
     int32             Status;
     CFE_SB_BufferD_t *BufDscPtr;
@@ -2141,7 +2143,7 @@ CFE_Status_t CFE_SB_TransmitBuffer(CFE_SB_Buffer_t *BufPtr, bool IncrementSequen
          */
         if (Status == CFE_SUCCESS)
         {
-            BufDscPtr->AutoSequence = IncrementSequenceCount;
+            BufDscPtr->NeedsUpdate = UpdateHeader;
             CFE_MSG_GetType(&BufPtr->Msg, &BufDscPtr->ContentType);
 
             /* Now broadcast the message, which consumes the buffer */
diff --git a/modules/sb/fsw/src/cfe_sb_priv.h b/modules/sb/fsw/src/cfe_sb_priv.h
index 9443c6094..737682936 100644
--- a/modules/sb/fsw/src/cfe_sb_priv.h
+++ b/modules/sb/fsw/src/cfe_sb_priv.h
@@ -150,7 +150,7 @@ typedef struct CFE_SB_BufferD
     size_t         ContentSize;   /**< Actual size of message content currently stored in the buffer */
     CFE_MSG_Type_t ContentType;   /**< Type of message content currently stored in the buffer */
 
-    bool AutoSequence; /**< If message should get its sequence number assigned from the route */
+    bool NeedsUpdate; /**< If message should get its header fields automatically updated */
 
     uint16 UseCount; /**< Number of active references to this buffer in the system */
 
diff --git a/modules/sb/ut-coverage/sb_UT.c b/modules/sb/ut-coverage/sb_UT.c
index ba6a3dded..78c89bab5 100644
--- a/modules/sb/ut-coverage/sb_UT.c
+++ b/modules/sb/ut-coverage/sb_UT.c
@@ -2850,7 +2850,7 @@ void Test_TransmitMsg_API(void)
     SB_UT_ADD_SUBTEST(Test_TransmitMsg_NoSubscribers);
     SB_UT_ADD_SUBTEST(Test_TransmitMsg_MaxMsgSizePlusOne);
     SB_UT_ADD_SUBTEST(Test_TransmitMsg_BasicSend);
-    SB_UT_ADD_SUBTEST(Test_TransmitMsg_SequenceCount);
+    SB_UT_ADD_SUBTEST(Test_TransmitMsg_UpdateHeader);
     SB_UT_ADD_SUBTEST(Test_TransmitMsg_QueuePutError);
     SB_UT_ADD_SUBTEST(Test_TransmitMsg_PipeFull);
     SB_UT_ADD_SUBTEST(Test_TransmitMsg_MsgLimitExceeded);
@@ -2962,9 +2962,9 @@ static int32 UT_CheckSetSequenceCount(void *UserObj, int32 StubRetcode, uint32 C
 }
 
 /*
-** Test successful send/receive for packet sequence count
+** Test successful send with header update
 */
-void Test_TransmitMsg_SequenceCount(void)
+void Test_TransmitMsg_UpdateHeader(void)
 {
     CFE_SB_PipeId_t         PipeId = CFE_SB_INVALID_PIPE;
     CFE_SB_MsgId_t          MsgId  = SB_UT_TLM_MID;
@@ -2977,8 +2977,8 @@ void Test_TransmitMsg_SequenceCount(void)
 
     memset(&TlmPkt, 0, sizeof(TlmPkt));
 
-    /* Set up hook for checking CFE_MSG_SetSequenceCount calls */
-    UT_SetHookFunction(UT_KEY(CFE_MSG_SetSequenceCount), UT_CheckSetSequenceCount, &SeqCnt);
+    /* Set up hook for checking CFE_MSG_UpdateHeader calls */
+    UT_SetHookFunction(UT_KEY(CFE_MSG_UpdateHeader), UT_CheckSetSequenceCount, &SeqCnt);
 
     CFE_UtAssert_SETUP(CFE_SB_CreatePipe(&PipeId, PipeDepth, "SeqCntTestPipe"));
     CFE_UtAssert_SETUP(CFE_SB_Subscribe(MsgId, PipeId));
@@ -2991,7 +2991,7 @@ void Test_TransmitMsg_SequenceCount(void)
     UT_SetDataBuffer(UT_KEY(CFE_MSG_GetType), &Type, sizeof(Type), false);
 
     CFE_UtAssert_SETUP(CFE_SB_TransmitMsg(CFE_MSG_PTR(TlmPkt.TelemetryHeader), true));
-    UtAssert_STUB_COUNT(CFE_MSG_SetSequenceCount, 1);
+    UtAssert_STUB_COUNT(CFE_MSG_UpdateHeader, 1);
     UtAssert_STUB_COUNT(CFE_MSG_GetNextSequenceCount, 1);
     UtAssert_INT32_EQ(SeqCnt, SeqCntExpected);
 
@@ -3002,7 +3002,7 @@ void Test_TransmitMsg_SequenceCount(void)
 
     /* Assert sequence count wasn't set */
     UtAssert_STUB_COUNT(CFE_MSG_GetNextSequenceCount, 1);
-    UtAssert_STUB_COUNT(CFE_MSG_SetSequenceCount, 1);
+    UtAssert_STUB_COUNT(CFE_MSG_UpdateHeader, 1);
 
     SeqCntExpected = 2;
     UT_SetDefaultReturnValue(UT_KEY(CFE_MSG_GetNextSequenceCount), SeqCntExpected);
@@ -3011,7 +3011,7 @@ void Test_TransmitMsg_SequenceCount(void)
     UT_SetDataBuffer(UT_KEY(CFE_MSG_GetType), &Type, sizeof(Type), false);
     CFE_UtAssert_SUCCESS(CFE_SB_TransmitMsg(CFE_MSG_PTR(TlmPkt.TelemetryHeader), true));
     UtAssert_INT32_EQ(SeqCnt, SeqCntExpected);
-    UtAssert_STUB_COUNT(CFE_MSG_SetSequenceCount, 2);
+    UtAssert_STUB_COUNT(CFE_MSG_UpdateHeader, 2);
     UtAssert_STUB_COUNT(CFE_MSG_GetNextSequenceCount, 2);
 
     CFE_UtAssert_EVENTCOUNT(2);
@@ -3025,7 +3025,7 @@ void Test_TransmitMsg_SequenceCount(void)
     UT_SetDataBuffer(UT_KEY(CFE_MSG_GetSize), &Size, sizeof(Size), false);
     UT_SetDataBuffer(UT_KEY(CFE_MSG_GetType), &Type, sizeof(Type), false);
     CFE_UtAssert_SETUP(CFE_SB_TransmitMsg(CFE_MSG_PTR(TlmPkt.TelemetryHeader), true)); /* increment to 3 */
-    UtAssert_STUB_COUNT(CFE_MSG_SetSequenceCount, 3);
+    UtAssert_STUB_COUNT(CFE_MSG_UpdateHeader, 3);
     UtAssert_STUB_COUNT(CFE_MSG_GetNextSequenceCount, 3);
 
     CFE_UtAssert_SETUP(CFE_SB_Subscribe(MsgId, PipeId)); /* resubscribe so we can receive a msg */
@@ -3037,7 +3037,7 @@ void Test_TransmitMsg_SequenceCount(void)
     UT_SetDataBuffer(UT_KEY(CFE_MSG_GetType), &Type, sizeof(Type), false);
     CFE_UtAssert_SETUP(CFE_SB_TransmitMsg(CFE_MSG_PTR(TlmPkt.TelemetryHeader), true)); /* increment to 4 */
     UtAssert_INT32_EQ(SeqCnt, SeqCntExpected);
-    UtAssert_STUB_COUNT(CFE_MSG_SetSequenceCount, 4);
+    UtAssert_STUB_COUNT(CFE_MSG_UpdateHeader, 4);
     UtAssert_STUB_COUNT(CFE_MSG_GetNextSequenceCount, 4);
 
     CFE_UtAssert_TEARDOWN(CFE_SB_DeletePipe(PipeId));
@@ -3288,8 +3288,8 @@ void Test_TransmitBuffer_IncrementSeqCnt(void)
     CFE_MSG_Size_t          Size = sizeof(SB_UT_Test_Tlm_t);
     CFE_MSG_Type_t          Type = CFE_MSG_Type_Tlm;
 
-    /* Set up hook for checking CFE_MSG_SetSequenceCount calls */
-    UT_SetHookFunction(UT_KEY(CFE_MSG_SetSequenceCount), UT_CheckSetSequenceCount, &SeqCnt);
+    /* Set up hook for checking CFE_MSG_UpdateHeader calls */
+    UT_SetHookFunction(UT_KEY(CFE_MSG_UpdateHeader), UT_CheckSetSequenceCount, &SeqCnt);
 
     CFE_UtAssert_SETUP(CFE_SB_CreatePipe(&PipeId, PipeDepth, "ZeroCpyTestPipe"));
 
diff --git a/modules/sb/ut-coverage/sb_UT.h b/modules/sb/ut-coverage/sb_UT.h
index ad510d305..6a4f59270 100644
--- a/modules/sb/ut-coverage/sb_UT.h
+++ b/modules/sb/ut-coverage/sb_UT.h
@@ -1854,7 +1854,7 @@ void Test_TransmitMsg_BasicSend(void);
 
 /*****************************************************************************/
 /**
-** \brief Test successful send/receive for packet sequence count
+** \brief Test successful send of messages with header update
 **
 ** \par Description
 **        This function tests successful send/receive for packet sequence
@@ -1866,7 +1866,7 @@ void Test_TransmitMsg_BasicSend(void);
 ** \returns
 **        This function does not return a value.
 ******************************************************************************/
-void Test_TransmitMsg_SequenceCount(void);
+void Test_TransmitMsg_UpdateHeader(void);
 
 /*****************************************************************************/
 /**
diff --git a/modules/tbl/fsw/src/cfe_tbl_internal.c b/modules/tbl/fsw/src/cfe_tbl_internal.c
index bb72f3477..18991d96e 100644
--- a/modules/tbl/fsw/src/cfe_tbl_internal.c
+++ b/modules/tbl/fsw/src/cfe_tbl_internal.c
@@ -1379,7 +1379,7 @@ int32 CFE_TBL_SendNotificationMsg(CFE_TBL_RegistryRec_t *RegRecPtr)
         CFE_TBL_Global.NotifyMsg.Payload.Parameter = RegRecPtr->NotificationParam;
 
         CFE_SB_TimeStampMsg(CFE_MSG_PTR(CFE_TBL_Global.NotifyMsg.CommandHeader));
-        Status = CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TBL_Global.NotifyMsg.CommandHeader), false);
+        Status = CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TBL_Global.NotifyMsg.CommandHeader), true);
 
         if (Status != CFE_SUCCESS)
         {
diff --git a/modules/time/fsw/src/cfe_time_tone.c b/modules/time/fsw/src/cfe_time_tone.c
index 9e8ca3a50..b3a431386 100644
--- a/modules/time/fsw/src/cfe_time_tone.c
+++ b/modules/time/fsw/src/cfe_time_tone.c
@@ -150,7 +150,7 @@ void CFE_TIME_ToneSend(void)
     /*
     ** Send "time at the tone" command data packet...
     */
-    CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TIME_Global.ToneDataCmd.CommandHeader), false);
+    CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TIME_Global.ToneDataCmd.CommandHeader), true);
 
     /*
     ** Count of "time at the tone" commands sent with internal data...
@@ -275,7 +275,7 @@ int32 CFE_TIME_ToneSendMET(CFE_TIME_SysTime_t NewMET)
             /*
             ** Send "time at the tone" command data packet...
             */
-            CFE_SB_TransmitMsg(&CFE_TIME_Global.ToneDataCmd.CommandHeader.Msg, false);
+            CFE_SB_TransmitMsg(&CFE_TIME_Global.ToneDataCmd.CommandHeader.Msg, true);
 
             /*
             ** Count of "time at the tone" commands sent with external data...
@@ -415,7 +415,7 @@ int32 CFE_TIME_ToneSendGPS(CFE_TIME_SysTime_t NewTime, int16 NewLeaps)
             /*
             ** Send "time at the tone" command data packet...
             */
-            CFE_SB_TransmitMsg(&CFE_TIME_Global.ToneDataCmd.CommandHeader.Msg, false);
+            CFE_SB_TransmitMsg(&CFE_TIME_Global.ToneDataCmd.CommandHeader.Msg, true);
 
             /*
             ** Count of "time at the tone" commands sent with external data...
@@ -555,7 +555,7 @@ int32 CFE_TIME_ToneSendTime(CFE_TIME_SysTime_t NewTime)
             /*
             ** Send "time at the tone" command data packet...
             */
-            CFE_SB_TransmitMsg(&CFE_TIME_Global.ToneDataCmd.CommandHeader.Msg, false);
+            CFE_SB_TransmitMsg(&CFE_TIME_Global.ToneDataCmd.CommandHeader.Msg, true);
 
             /*
             ** Count of "time at the tone" commands sent with external data...
@@ -1088,7 +1088,7 @@ void CFE_TIME_Tone1HzTask(void)
         /*
         ** Send tone signal command packet...
         */
-        CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TIME_Global.ToneSignalCmd.CommandHeader), false);
+        CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TIME_Global.ToneSignalCmd.CommandHeader), true);
 
 #if (CFE_MISSION_TIME_CFG_FAKE_TONE == true)
         /*
@@ -1096,7 +1096,7 @@ void CFE_TIME_Tone1HzTask(void)
         ** to send the tone to other time clients.
         ** (this is done by scheduler in non-fake mode)
         */
-        CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TIME_Global.ToneSendCmd.CommandHeader), false);
+        CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TIME_Global.ToneSendCmd.CommandHeader), true);
 #endif
 
         /*
@@ -1287,7 +1287,7 @@ void CFE_TIME_Local1HzTask(void)
         ** This used to be optional in previous CFE versions, but it is now required
         ** as TIME subscribes to this itself to do state machine tasks.
         */
-        CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TIME_Global.Local1HzCmd.CommandHeader), false);
+        CFE_SB_TransmitMsg(CFE_MSG_PTR(CFE_TIME_Global.Local1HzCmd.CommandHeader), true);
 
         CFE_TIME_Global.LocalTaskCounter++;