diff --git a/CHANGELOG.md b/CHANGELOG.md
index fa5ed5a2..9f4f5337 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,10 @@ list yields a list of all related PRs for each release.
 
 # [unreleased]
 
+## Fixed
+
+- PLOC SUPV: Minor adaptions and important bugfix for UART manager
+
 ## Added
 
 - First version of ACS controller
diff --git a/linux/devices/devicedefinitions/PlocMPSoCDefinitions.h b/linux/devices/devicedefinitions/PlocMPSoCDefinitions.h
index 8a88a716..9cb609bf 100644
--- a/linux/devices/devicedefinitions/PlocMPSoCDefinitions.h
+++ b/linux/devices/devicedefinitions/PlocMPSoCDefinitions.h
@@ -152,7 +152,7 @@ class TcBase : public ploc::SpTcBase, public MPSoCReturnValuesIF {
    *        sent and received packets.
    */
   TcBase(ploc::SpTcParams params, uint16_t apid, uint16_t sequenceCount)
-      : ploc::SpTcBase(params, apid, sequenceCount) {
+      : ploc::SpTcBase(params, apid, 0, sequenceCount) {
     spParams.setFullPayloadLen(INIT_LENGTH);
   }
 
diff --git a/linux/devices/devicedefinitions/PlocSupervisorDefinitions.h b/linux/devices/devicedefinitions/PlocSupervisorDefinitions.h
index cb0639fa..ffc310f0 100644
--- a/linux/devices/devicedefinitions/PlocSupervisorDefinitions.h
+++ b/linux/devices/devicedefinitions/PlocSupervisorDefinitions.h
@@ -730,17 +730,13 @@ class FactoryReset : public TcBase {
       : TcBase(params, Apid::DATA_LOGGER,
                static_cast<uint8_t>(tc::DataLoggerServiceId::FACTORY_RESET), 0) {}
 
-  ReturnValue_t buildPacket(std::optional<uint8_t> op) {
-    if (op) {
-      setLenFromPayloadLen(1);
-    }
+  ReturnValue_t buildPacket(uint8_t op) {
+    setLenFromPayloadLen(1);
     auto res = checkSizeAndSerializeHeader();
     if (res != returnvalue::OK) {
       return res;
     }
-    if (op) {
-      payloadStart[0] = op.value();
-    }
+    payloadStart[0] = op;
     return calcAndSetCrc();
   }
 
diff --git a/linux/devices/ploc/PlocMPSoCHandler.cpp b/linux/devices/ploc/PlocMPSoCHandler.cpp
index 28513314..2ac58335 100644
--- a/linux/devices/ploc/PlocMPSoCHandler.cpp
+++ b/linux/devices/ploc/PlocMPSoCHandler.cpp
@@ -184,12 +184,14 @@ void PlocMPSoCHandler::doShutDown() {
       powerState = PowerState::SHUTDOWN;
       break;
     case PowerState::OFF:
+      sequenceCount = 0;
       setMode(_MODE_POWER_DOWN);
       break;
     default:
       break;
   }
 #else
+  sequenceCount = 0;
   uartIsolatorSwitch.pullLow();
   setMode(_MODE_POWER_DOWN);
   powerState = PowerState::OFF;
@@ -340,7 +342,6 @@ ReturnValue_t PlocMPSoCHandler::scanForReply(const uint8_t* start, size_t remain
     }
   }
 
-  sequenceCount++;
   uint16_t recvSeqCnt = (*(start + 2) << 8 | *(start + 3)) & PACKET_SEQUENCE_COUNT_MASK;
   if (recvSeqCnt != sequenceCount) {
     triggerEvent(MPSOC_HANDLER_SEQUENCE_COUNT_MISMATCH, sequenceCount, recvSeqCnt);
@@ -403,11 +404,9 @@ void PlocMPSoCHandler::handleEvent(EventMessage* eventMessage) {
 ReturnValue_t PlocMPSoCHandler::prepareTcMemWrite(const uint8_t* commandData,
                                                   size_t commandDataLen) {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcMemWrite tcMemWrite(spParams, sequenceCount);
   result = tcMemWrite.buildPacket(commandData, commandDataLen);
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcMemWrite.getFullPacketLen());
@@ -417,11 +416,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcMemWrite(const uint8_t* commandData,
 ReturnValue_t PlocMPSoCHandler::prepareTcMemRead(const uint8_t* commandData,
                                                  size_t commandDataLen) {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcMemRead tcMemRead(spParams, sequenceCount);
   result = tcMemRead.buildPacket(commandData, commandDataLen);
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcMemRead.getFullPacketLen());
@@ -435,12 +432,10 @@ ReturnValue_t PlocMPSoCHandler::prepareTcFlashDelete(const uint8_t* commandData,
     return MPSoCReturnValuesIF::NAME_TOO_LONG;
   }
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcFlashDelete tcFlashDelete(spParams, sequenceCount);
   result = tcFlashDelete.buildPacket(
       std::string(reinterpret_cast<const char*>(commandData), commandDataLen));
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcFlashDelete.getFullPacketLen());
@@ -450,11 +445,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcFlashDelete(const uint8_t* commandData,
 ReturnValue_t PlocMPSoCHandler::prepareTcReplayStart(const uint8_t* commandData,
                                                      size_t commandDataLen) {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcReplayStart tcReplayStart(spParams, sequenceCount);
   result = tcReplayStart.buildPacket(commandData, commandDataLen);
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcReplayStart.getFullPacketLen());
@@ -463,11 +456,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcReplayStart(const uint8_t* commandData,
 
 ReturnValue_t PlocMPSoCHandler::prepareTcReplayStop() {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcReplayStop tcReplayStop(spParams, sequenceCount);
   result = tcReplayStop.buildPacket();
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcReplayStop.getFullPacketLen());
@@ -477,11 +468,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcReplayStop() {
 ReturnValue_t PlocMPSoCHandler::prepareTcDownlinkPwrOn(const uint8_t* commandData,
                                                        size_t commandDataLen) {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcDownlinkPwrOn tcDownlinkPwrOn(spParams, sequenceCount);
   result = tcDownlinkPwrOn.buildPacket(commandData, commandDataLen);
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcDownlinkPwrOn.getFullPacketLen());
@@ -490,11 +479,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcDownlinkPwrOn(const uint8_t* commandDat
 
 ReturnValue_t PlocMPSoCHandler::prepareTcDownlinkPwrOff() {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcDownlinkPwrOff tcDownlinkPwrOff(spParams, sequenceCount);
   result = tcDownlinkPwrOff.buildPacket();
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcDownlinkPwrOff.getFullPacketLen());
@@ -504,11 +491,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcDownlinkPwrOff() {
 ReturnValue_t PlocMPSoCHandler::prepareTcReplayWriteSequence(const uint8_t* commandData,
                                                              size_t commandDataLen) {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcReplayWriteSeq tcReplayWriteSeq(spParams, sequenceCount);
   result = tcReplayWriteSeq.buildPacket(commandData, commandDataLen);
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcReplayWriteSeq.getFullPacketLen());
@@ -517,11 +502,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcReplayWriteSequence(const uint8_t* comm
 
 ReturnValue_t PlocMPSoCHandler::prepareTcModeReplay() {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcModeReplay tcModeReplay(spParams, sequenceCount);
   result = tcModeReplay.buildPacket();
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcModeReplay.getFullPacketLen());
@@ -530,11 +513,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcModeReplay() {
 
 ReturnValue_t PlocMPSoCHandler::prepareTcModeIdle() {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcModeIdle tcModeIdle(spParams, sequenceCount);
   result = tcModeIdle.buildPacket();
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcModeIdle.getFullPacketLen());
@@ -544,11 +525,9 @@ ReturnValue_t PlocMPSoCHandler::prepareTcModeIdle() {
 ReturnValue_t PlocMPSoCHandler::prepareTcCamCmdSend(const uint8_t* commandData,
                                                     size_t commandDataLen) {
   ReturnValue_t result = returnvalue::OK;
-  sequenceCount++;
   mpsoc::TcCamcmdSend tcCamCmdSend(spParams, sequenceCount);
   result = tcCamCmdSend.buildPacket(commandData, commandDataLen);
   if (result != returnvalue::OK) {
-    sequenceCount--;
     return result;
   }
   finishTcPrep(tcCamCmdSend.getFullPacketLen());
@@ -560,6 +539,7 @@ void PlocMPSoCHandler::finishTcPrep(size_t packetLen) {
   nextReplyId = mpsoc::ACK_REPORT;
   rawPacket = commandBuffer;
   rawPacketLen = packetLen;
+  sequenceCount++;
 }
 
 ReturnValue_t PlocMPSoCHandler::verifyPacket(const uint8_t* start, size_t foundLen) {
diff --git a/linux/devices/ploc/PlocMPSoCHandler.h b/linux/devices/ploc/PlocMPSoCHandler.h
index a7d7a427..99a12515 100644
--- a/linux/devices/ploc/PlocMPSoCHandler.h
+++ b/linux/devices/ploc/PlocMPSoCHandler.h
@@ -107,10 +107,7 @@ class PlocMPSoCHandler : public DeviceHandlerBase, public CommandsActionsIF {
   MessageQueueIF* eventQueue = nullptr;
   MessageQueueIF* commandActionHelperQueue = nullptr;
 
-  // Initiate the sequence count with the maximum value. It is incremented before
-  // a packet is sent, so the first value will be 0 accordingly using
-  // the wrap around of the counter.
-  SourceSequenceCounter sequenceCount = SourceSequenceCounter(ccsds::LIMIT_SEQUENCE_COUNT - 1);
+  SourceSequenceCounter sequenceCount = SourceSequenceCounter(0);
 
   uint8_t commandBuffer[mpsoc::MAX_COMMAND_SIZE];
   SpacePacketCreator creator;
diff --git a/linux/devices/ploc/PlocSupervisorHandler.cpp b/linux/devices/ploc/PlocSupervisorHandler.cpp
index 08c63b1a..17657b50 100644
--- a/linux/devices/ploc/PlocSupervisorHandler.cpp
+++ b/linux/devices/ploc/PlocSupervisorHandler.cpp
@@ -136,29 +136,34 @@ ReturnValue_t PlocSupervisorHandler::executeAction(ActionId_t actionId,
 }
 
 void PlocSupervisorHandler::doStartUp() {
-  if (setTimeDuringStartup) {
-    if (startupState == StartupState::OFF) {
-      bootTimeout.resetTimer();
-      startupState = StartupState::BOOTING;
-    }
-    if (startupState == StartupState::BOOTING) {
-      if (bootTimeout.hasTimedOut()) {
-        uartIsolatorSwitch.pullHigh();
-        uartManager.start();
+  if (startupState == StartupState::OFF) {
+    bootTimeout.resetTimer();
+    startupState = StartupState::BOOTING;
+  }
+  if (startupState == StartupState::BOOTING) {
+    if (bootTimeout.hasTimedOut()) {
+      uartIsolatorSwitch.pullHigh();
+      uartManager.start();
+      if (SET_TIME_DURING_BOOT) {
         startupState = StartupState::SET_TIME;
+      } else {
+        startupState = StartupState::ON;
       }
     }
-    if (startupState == StartupState::ON) {
-      setMode(_MODE_TO_ON);
-    }
-  } else {
-    uartIsolatorSwitch.pullHigh();
+  }
+  if (startupState == StartupState::SET_TIME_EXECUTING) {
+    startupState = StartupState::ON;
+  }
+  if (startupState == StartupState::ON) {
     setMode(_MODE_TO_ON);
   }
 }
 
 void PlocSupervisorHandler::doShutDown() {
   setMode(_MODE_POWER_DOWN);
+  shutdownCmdSent = false;
+  packetInBuffer = false;
+  nextReplyId = supv::NONE;
   uartManager.stop();
   uartIsolatorSwitch.pullLow();
   startupState = StartupState::OFF;
@@ -1467,11 +1472,10 @@ ReturnValue_t PlocSupervisorHandler::prepareReadGpioCmd(const uint8_t* commandDa
 ReturnValue_t PlocSupervisorHandler::prepareFactoryResetCmd(const uint8_t* commandData,
                                                             size_t len) {
   FactoryReset resetCmd(spParams);
-  std::optional<uint8_t> op;
-  if (len > 0) {
-    op = commandData[0];
+  if (len < 1) {
+    return HasActionsIF::INVALID_PARAMETERS;
   }
-  ReturnValue_t result = resetCmd.buildPacket(op);
+  ReturnValue_t result = resetCmd.buildPacket(commandData[0]);
   if (result != returnvalue::OK) {
     return result;
   }
@@ -1897,9 +1901,8 @@ ReturnValue_t PlocSupervisorHandler::handleExecutionSuccessReport(ExecutionRepor
       break;
     }
     case supv::SET_TIME_REF: {
-      if (startupState == StartupState::SET_TIME_EXECUTING) {
-        startupState = StartupState::ON;
-      }
+      // We could only allow proper bootup when the time was set successfully, but
+      // this makes debugging difficult.
       break;
     }
     default:
diff --git a/linux/devices/ploc/PlocSupervisorHandler.h b/linux/devices/ploc/PlocSupervisorHandler.h
index 4ffe4166..52e2619b 100644
--- a/linux/devices/ploc/PlocSupervisorHandler.h
+++ b/linux/devices/ploc/PlocSupervisorHandler.h
@@ -97,11 +97,11 @@ class PlocSupervisorHandler : public DeviceHandlerBase {
   static const uint32_t COPY_ADC_TO_MRAM_TIMEOUT = 70000;
   // 60 s
   static const uint32_t MRAM_DUMP_TIMEOUT = 60000;
-  // 2 s
-  static const uint32_t BOOT_TIMEOUT = 2000;
+  // 4 s
+  static const uint32_t BOOT_TIMEOUT = 4000;
   enum class StartupState : uint8_t { OFF, BOOTING, SET_TIME, SET_TIME_EXECUTING, ON };
 
-  bool setTimeDuringStartup = true;
+  static constexpr bool SET_TIME_DURING_BOOT = true;
 
   StartupState startupState = StartupState::OFF;
 
@@ -138,8 +138,6 @@ class PlocSupervisorHandler : public DeviceHandlerBase {
   uint32_t receivedMramDumpPackets = 0;
   /** Set to true as soon as a complete space packet is present in the spacePacketBuffer */
   bool packetInBuffer = false;
-  /** Points to the next free position in the space packet buffer */
-  uint16_t bufferTop = 0;
 
   /** This buffer is used to concatenate space packets received in two different read steps */
   uint8_t spacePacketBuffer[supv::MAX_PACKET_SIZE];
diff --git a/linux/devices/ploc/PlocSupvUartMan.cpp b/linux/devices/ploc/PlocSupvUartMan.cpp
index a246d97c..1fd2b841 100644
--- a/linux/devices/ploc/PlocSupvUartMan.cpp
+++ b/linux/devices/ploc/PlocSupvUartMan.cpp
@@ -100,6 +100,7 @@ ReturnValue_t PlocSupvUartManager::performOperation(uint8_t operationCode) {
     state = InternalState::SLEEPING;
     lock->unlockMutex();
     semaphore->acquire();
+    putTaskToSleep = false;
     while (true) {
       if (putTaskToSleep) {
         performUartShutdown();
@@ -295,11 +296,14 @@ void PlocSupvUartManager::stop() {
 }
 
 void PlocSupvUartManager::start() {
-  MutexGuard mg(lock);
-  if (state != InternalState::SLEEPING and state != InternalState::GO_TO_SLEEP) {
-    return;
+  {
+    MutexGuard mg(lock);
+    if (state != InternalState::SLEEPING and state != InternalState::GO_TO_SLEEP) {
+      return;
+    }
+    state = InternalState::DEFAULT;
   }
-  state = InternalState::DEFAULT;
+
   semaphore->release();
 }
 
diff --git a/tmtc b/tmtc
index 9016d3d9..5c675560 160000
--- a/tmtc
+++ b/tmtc
@@ -1 +1 @@
-Subproject commit 9016d3d992bb6c5aa8dd11065ceb913b8ba88491
+Subproject commit 5c675560eadadfbb5e674d9be87c206df09d1771