Index: firmware/App/Modes/ModeTreatment.c
===================================================================
diff -u -r9936f4fe6267a4e682709db5c2383d8f9cbfeb82 -rc3c728b43a2d5c9faf461d5e635f62e5fc32da27
--- firmware/App/Modes/ModeTreatment.c	(.../ModeTreatment.c)	(revision 9936f4fe6267a4e682709db5c2383d8f9cbfeb82)
+++ firmware/App/Modes/ModeTreatment.c	(.../ModeTreatment.c)	(revision c3c728b43a2d5c9faf461d5e635f62e5fc32da27)
@@ -8,7 +8,7 @@
 * @file    ModeTreatment.c
 *
 * @author  (last)      Dara Navaei
-* @date    (last)      12-Jul-2023
+* @date    (last)      24-Jul-2023
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  05-Nov-2019
@@ -767,14 +767,7 @@
     // Update treatment time (unless delivering a saline bolus)
     if ( dialysisState != DIALYSIS_SALINE_BOLUS_STATE )
     {
-#ifdef DIALYZER_REPRIME_ENABLED
-        if ( dialysisState != DIALYSIS_DIALYZER_REPRIME_STATE )
-        {
-#endif
         treatmentTimeMS += msSinceLast;
-#ifdef DIALYZER_REPRIME_ENABLED
-        }
-#endif
     }
     lastTreatmentTimeStamp = newTime;
 
@@ -925,16 +918,26 @@
  * @brief
  * The handleTreatmentRecircState function executes the re-circulate state of the
  * Treatment Mode state machine.
- * @details Inputs: none
- * @details Outputs: treatment re-circulate sub-mode executed.
+ * @details Inputs: endTreatmentAlarmResponseRequest, rinsebackToStoppedRequest,
+ * endTreatmentRequest
+ * @details Outputs: sendLastTreatmentPeriodicData
  * @return next treatment mode state
  *************************************************************************/
 static TREATMENT_STATE_T handleTreatmentRecircState( void )
 {
     TREATMENT_STATE_T result = TREATMENT_RECIRC_STATE;
 
-    // Execute treatment re-circ sub-mode
-    execTreatmentRecirc();
+    // If user requests treatment end, end treatment
+    if ( TRUE == endTreatmentAlarmResponseRequest )
+    {
+        sendLastTreatmentPeriodicData = TRUE;
+        requestNewOperationMode( MODE_POST );
+    }
+    else
+    {
+        // Execute treatment re-circ sub-mode
+        execTreatmentRecirc();
+    }
 
     // Handle signals from treatment re-circ sub-mode
     if ( TRUE == rinsebackToStoppedRequest )
@@ -1096,6 +1099,9 @@
     S32 timeDiff = 0;
     F32 rateDiff = 0.0;
     HD_OP_MODE_T currMode = getCurrentOperationMode();
+    S32 txSecRem = CALC_TREAT_TIME_REMAINING_IN_SECS();
+    S32 txMinEla = CALC_ELAPSED_TREAT_TIME_IN_SECS() / SEC_PER_MIN;
+    F32 txMinRem = (F32)txSecRem / (F32)SEC_PER_MIN;
 
     // Reset pending UF/time settings changes to current values in case request is rejected
     pendingUFVolumeChange = presMaxUFVolumeML;
@@ -1110,9 +1116,12 @@
     {
         DIALYSIS_STATE_T currDialysisState = getDialysisState();
         UF_STATE_T currUFState = getUltrafiltrationState();
-        F32 uFRate = uFVolume / ((F32)presTreatmentTimeSecs / (F32)SEC_PER_MIN);                // What UF rate would be if user selected to adjust it
-        U32 trtTime = (S32)( uFVolume / presUFRate ) + 1;                                       // What the treatment duration would be if user selected to adjust it
-        U32 dialVolume = getTreatmentParameterU32( TREATMENT_PARAM_DIALYSATE_FLOW ) * trtTime;  // What dialysate volume would be if user selected to adjust time
+        F32 colUFVol = getUltrafiltrationReferenceVolume();                                          // How much UF volume have we taken so far?
+        F32 remUFVol = uFVolume - colUFVol;                                                          // What would remaining UF volume be after subtracting UF volume already taken
+        F32 remUFVolCap = RANGE( remUFVol, 0.0F, (F32)MAX_UF_VOLUME_ML );                            // Enforce valid range on remaining UF volume
+        F32 uFRate = remUFVolCap / txMinRem;                                                         // What UF rate would be if user selected to adjust it
+        U32 trtTime = ( fabs( presUFRate ) < NEARLY_ZERO ? txMinEla + 1 : (S32)( remUFVolCap / presUFRate ) + txMinEla + 1 ); // What the treatment duration would be if user selected to adjust it
+        U32 dialVolume = getTreatmentParameterU32( TREATMENT_PARAM_DIALYSATE_FLOW ) * trtTime;       // What dialysate volume would be if user selected to adjust time
 
         // UF should already be paused but let's make sure.
         if ( ( TREATMENT_DIALYSIS_STATE == currentTreatmentState ) &&
@@ -1137,19 +1146,8 @@
         {
             pendingUFRateChange = 0.0;
         }
-        // Verify treatment duration change would be valid (leave zero if not valid - UI will disable option)
-        if ( ( trtTime <= MAX_TREATMENT_TIME_MINUTES ) && ( trtTime >= getMinTreatmentTimeInMinutes() ) &&
-             ( dialVolume <= MAX_DIALYSATE_VOLUME_ML ) )
-        {
-            result = TRUE;
-            pendingUFVolumeChange = uFVolume;
-            pendingTreatmentTimeChange = trtTime;
-            timeDiff = trtTime - ( (U32)( (F32)presTreatmentTimeSecs / (F32)SEC_PER_MIN ) + 1 );
-        }
-        else
-        {
-            pendingTreatmentTimeChange = 0;
-        }
+        // Treatment duration change is now never valid - leave zero - UI will disable option)
+        pendingTreatmentTimeChange = 0;
         // If neither option works, reject for UF rate
         if ( FALSE == result )
         {
@@ -1211,14 +1209,9 @@
         presMaxUFVolumeML = pendingUFVolumeChange;
         setTreatmentParameterF32( TREATMENT_PARAM_UF_VOLUME, ( presMaxUFVolumeML / (F32)ML_PER_LITER ) );
 
-        // Which setting does user want to adjust to accommodate the UF volume change? (treatment time or UF rate)
-        if ( UF_ADJ_TREATMENT_TIME == adjustment )
+        // User should only allow UF rate adjustment to achieve UF volume change
+        if ( UF_ADJ_UF_RATE == adjustment )
         {
-            presTreatmentTimeSecs = pendingTreatmentTimeChange * SEC_PER_MIN;
-            setTreatmentParameterU32( TREATMENT_PARAM_TREATMENT_DURATION, ( presTreatmentTimeSecs / SEC_PER_MIN ) );
-        }
-        else // Must be adjusting UF rate then
-        {
             sendTreatmentLogEventData( UF_RATE_CHANGE_EVENT, presUFRate, pendingUFRateChange );
             presUFRate = pendingUFRateChange;
             signalInitiatePressureStabilization();
@@ -1455,11 +1448,6 @@
         payload.txEndState = getCurrentTreatmentEndState();
         payload.heparinState = getHeparinState();
         payload.dialysisState = getDialysisState();
-#ifdef DIALYZER_REPRIME_ENABLED
-        payload.dlzReprimeState = getDialyzerRePrimeState();
-#else
-        payload.dlzReprimeState = 0;
-#endif
 
         broadcastData( MSG_ID_TREATMENT_STATE_DATA, COMM_BUFFER_OUT_CAN_HD_BROADCAST, (U08*)&payload, sizeof( TREATMENT_STATE_DATA_T ) );
         treatmentStateBroadcastTimerCtr = 0;