diff --git a/DRAMSys/analyzer/scripts/tests.py b/DRAMSys/analyzer/scripts/tests.py
index 7823da5a..a7e26334 100755
--- a/DRAMSys/analyzer/scripts/tests.py
+++ b/DRAMSys/analyzer/scripts/tests.py
@@ -259,7 +259,7 @@ def phase_transitions_are_valid(connection):
         validTransitions['REFB'] = set(['ACT', 'REFB', 'PDNPB', 'SREFB'])
 
         validTransitions['PDNAB'] = set(['PRE', 'RD', 'RDA', 'WR', 'WRA', 'REFB'])
-        validTransitions['PDNPB'] = set(['ACT', 'REFB'])
+        validTransitions['PDNPB'] = set(['ACT', 'REFB', 'SREFB'])
         validTransitions['SREFB'] = set(['ACT'])
     else:
         validTransitions['PRE'] = set(['ACT', 'PRE_ALL'])
@@ -274,7 +274,7 @@ def phase_transitions_are_valid(connection):
         validTransitions['REFA'] = set(['PRE_ALL', 'ACT', 'REFA', 'PDNA', 'PDNP', 'SREF'])
 
         validTransitions['PDNA'] = set(['PRE', 'PRE_ALL', 'ACT', 'RD', 'RDA', 'WR', 'WRA', 'REFA', 'PDNA', 'PDNP'])
-        validTransitions['PDNP'] = set(['PRE_ALL', 'ACT', 'REFA', 'PDNA', 'PDNP'])
+        validTransitions['PDNP'] = set(['PRE_ALL', 'ACT', 'REFA', 'PDNA', 'PDNP', 'SREF'])
         validTransitions['SREF'] = set(['PRE_ALL', 'ACT', 'REFA', 'PDNA', 'PDNP'])
 
     if (dramconfig.bankwiseLogic == "1"):
diff --git a/DRAMSys/simulator/src/controller/core/ControllerCore.cpp b/DRAMSys/simulator/src/controller/core/ControllerCore.cpp
index 57233afd..8de6d3f5 100644
--- a/DRAMSys/simulator/src/controller/core/ControllerCore.cpp
+++ b/DRAMSys/simulator/src/controller/core/ControllerCore.cpp
@@ -134,11 +134,19 @@ void ControllerCore::triggerRefresh(tlm::tlm_generic_payload& payload)
 
         state->cleanUp(time);
 
-        if (!refreshManager->isInvalidated(payload, time) && !powerDownManager->isInSelfRefresh(bank))
-        {
+        if (!refreshManager->isInvalidated(payload, time) && !powerDownManager->isInSelfRefresh(bank)) {
             printDebugMessage("Triggering refresh on bank " + to_string(bank.ID()));
             powerDownManager->wakeUpForRefresh(bank, time); //expects PDNA and PDNP to exit without delay
-            refreshManager->scheduleRefresh(payload, time);
+            bool pdnpToSrefTransition = false;
+            if (config.PowerDownMode == EPowerDownMode::Staggered) {
+                    pdnpToSrefTransition = state->getLastCommand(Command::PDNPX,bank).getStart() >= time;
+            }
+            if (pdnpToSrefTransition) {
+                powerDownManager->sleep(bank,time);
+            }
+            else {
+                refreshManager->scheduleRefresh(payload, time);
+            }
         }
     }
 }