diff --git a/CHANGELOG.md b/CHANGELOG.md
index d3d64dce..f485e458 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,10 +24,19 @@ change warranting a new major release:
 
 ## Changed
 
+- Remove 2 TCS threads.
+- Move low level polling into ACS PST, move high level device handlers into TCS system task.
 - ActCmds now returns command vectors as integers as required by the actuators
   and scales them to the appropriate range
 - All RwHandler are now polled five times per ACS cycle
 
+# [v1.27.1] 2023-02-13
+
+## Fixed
+
+- Fix for SPI ComIF: Set transfer size to 0 for failed transfers
+- Fix shadowing issue with locks in MAX31865 low level handler
+
 # [v1.27.0] 2023-02-13
 
 eive-tmtc: v2.12.5
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8af127a1..782993be 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,7 +11,7 @@ cmake_minimum_required(VERSION 3.13)
 
 set(OBSW_VERSION_MAJOR 1)
 set(OBSW_VERSION_MINOR 27)
-set(OBSW_VERSION_REVISION 0)
+set(OBSW_VERSION_REVISION 1)
 
 # set(CMAKE_VERBOSE TRUE)
 
diff --git a/bsp_q7s/core/scheduling.cpp b/bsp_q7s/core/scheduling.cpp
index cc3108e8..2aad7a23 100644
--- a/bsp_q7s/core/scheduling.cpp
+++ b/bsp_q7s/core/scheduling.cpp
@@ -214,21 +214,9 @@ void scheduling::initTasks() {
   }
 #endif
 
-#if OBSW_ADD_RTD_DEVICES == 1
-  PeriodicTaskIF* tcsPollingTask = factory->createPeriodicTask(
-      "TCS_POLLING_TASK", 75, PeriodicTaskIF::MINIMUM_STACK_SIZE * 2, 0.5, missedDeadlineFunc);
-  result = tcsPollingTask->addComponent(objects::SPI_RTD_COM_IF);
-  if (result != returnvalue::OK) {
-    scheduling::printAddObjectError("SPI_RTD_POLLING", objects::SPI_RTD_COM_IF);
-  }
-
-  PeriodicTaskIF* tcsTask = factory->createPeriodicTask(
-      "TCS_TASK", 55, PeriodicTaskIF::MINIMUM_STACK_SIZE, 0.8, missedDeadlineFunc);
-  scheduling::scheduleRtdSensors(tcsTask);
-#endif
-
   PeriodicTaskIF* tcsSystemTask = factory->createPeriodicTask(
-      "TCS_TASK", 45, PeriodicTaskIF::MINIMUM_STACK_SIZE, 0.5, missedDeadlineFunc);
+      "TCS_TASK", 55, PeriodicTaskIF::MINIMUM_STACK_SIZE, 0.5, missedDeadlineFunc);
+  scheduling::scheduleRtdSensors(tcsSystemTask);
   result = tcsSystemTask->addComponent(objects::TCS_SUBSYSTEM);
   if (result != returnvalue::OK) {
     scheduling::printAddObjectError("TCS_SUBSYSTEM", objects::TCS_SUBSYSTEM);
@@ -364,10 +352,6 @@ void scheduling::initTasks() {
   gpsTask->startTask();
 #endif
   acsSysTask->startTask();
-#if OBSW_ADD_RTD_DEVICES == 1
-  tcsPollingTask->startTask();
-  tcsTask->startTask();
-#endif /* OBSW_ADD_RTD_DEVICES == 1 */
   if (not tcsSystemTask->isEmpty()) {
     tcsSystemTask->startTask();
   }
@@ -394,7 +378,7 @@ void scheduling::createPstTasks(TaskFactory& factory, TaskDeadlineMissedFunction
 #endif
   FixedTimeslotTaskIF* acsPst = factory.createFixedTimeslotTask(
       "ACS_PST", 85, PeriodicTaskIF::MINIMUM_STACK_SIZE * 2, acsPstPeriod, missedDeadlineFunc);
-  result = pst::pstAcs(acsPst, cfg);
+  result = pst::pstTcsAndAcs(acsPst, cfg);
   if (result != returnvalue::OK) {
     if (result == FixedTimeslotTaskIF::SLOT_LIST_EMPTY) {
       sif::warning << "scheduling::initTasks: ACS PST is empty" << std::endl;
diff --git a/fsfw b/fsfw
index dac2d210..f0b8457b 160000
--- a/fsfw
+++ b/fsfw
@@ -1 +1 @@
-Subproject commit dac2d210b597adfaf45bd5ae6a4c027599927601
+Subproject commit f0b8457ba2d9a34a42b10314c3cdccfd46ebf168
diff --git a/linux/devices/Max31865RtdLowlevelHandler.cpp b/linux/devices/Max31865RtdLowlevelHandler.cpp
index a6fe2061..52a107dc 100644
--- a/linux/devices/Max31865RtdLowlevelHandler.cpp
+++ b/linux/devices/Max31865RtdLowlevelHandler.cpp
@@ -70,8 +70,8 @@ bool Max31865RtdReader::periodicInitHandling() {
       return false;
     }
     if ((rtd->on or rtd->db.active) and not rtd->db.configured and rtd->cd.hasTimedOut()) {
-      ManualCsLockWrapper mg(csLock, gpioIF, rtd->spiCookie, csTimeoutType, csTimeoutMs);
-      if (mg.lockResult != returnvalue::OK or mg.gpioResult != returnvalue::OK) {
+      ManualCsLockWrapper mg1(csLock, gpioIF, rtd->spiCookie, csTimeoutType, csTimeoutMs);
+      if (mg1.lockResult != returnvalue::OK or mg1.gpioResult != returnvalue::OK) {
         sif::error << "Max31865RtdReader::periodicInitHandling: Manual CS lock failed" << std::endl;
         continue;
       }
@@ -153,8 +153,8 @@ ReturnValue_t Max31865RtdReader::periodicReadHandling() {
       return returnvalue::FAILED;
     }
     if (rtdIsActive(rtd->idx)) {
-      ManualCsLockWrapper mg(csLock, gpioIF, rtd->spiCookie, csTimeoutType, csTimeoutMs);
-      if (mg.lockResult != returnvalue::OK or mg.gpioResult != returnvalue::OK) {
+      ManualCsLockWrapper mg1(csLock, gpioIF, rtd->spiCookie, csTimeoutType, csTimeoutMs);
+      if (mg1.lockResult != returnvalue::OK or mg1.gpioResult != returnvalue::OK) {
         sif::error << "Max31865RtdReader::periodicInitHandling: Manual CS lock failed" << std::endl;
         continue;
       }
diff --git a/linux/fsfwconfig/pollingsequence/pollingSequenceFactory.cpp b/linux/fsfwconfig/pollingsequence/pollingSequenceFactory.cpp
index 6b184f58..31606768 100644
--- a/linux/fsfwconfig/pollingsequence/pollingSequenceFactory.cpp
+++ b/linux/fsfwconfig/pollingsequence/pollingSequenceFactory.cpp
@@ -184,7 +184,7 @@ ReturnValue_t pst::pstTest(FixedTimeslotTaskIF *thisSequence) {
   return returnvalue::OK;
 }
 
-ReturnValue_t pst::pstAcs(FixedTimeslotTaskIF *thisSequence, AcsPstCfg cfg) {
+ReturnValue_t pst::pstTcsAndAcs(FixedTimeslotTaskIF *thisSequence, AcsPstCfg cfg) {
   /* Length of a communication cycle */
   uint32_t length = thisSequence->getPeriodMs();
   bool enableAside = true;
@@ -807,5 +807,6 @@ ReturnValue_t pst::pstAcs(FixedTimeslotTaskIF *thisSequence, AcsPstCfg cfg) {
     thisSequence->addSlot(objects::RW4, length * config::acs::SCHED_BLOCK_2_PERIOD,
                           DeviceHandlerIF::GET_READ);
   }
+  thisSequence->addSlot(objects::SPI_RTD_COM_IF, length * 0.5, 0);
   return returnvalue::OK;
 }
diff --git a/linux/fsfwconfig/pollingsequence/pollingSequenceFactory.h b/linux/fsfwconfig/pollingsequence/pollingSequenceFactory.h
index 3e5ead52..99fba4ad 100644
--- a/linux/fsfwconfig/pollingsequence/pollingSequenceFactory.h
+++ b/linux/fsfwconfig/pollingsequence/pollingSequenceFactory.h
@@ -49,7 +49,7 @@ ReturnValue_t pstGompaceCan(FixedTimeslotTaskIF* thisSequence);
 
 ReturnValue_t pstSpiAndSyrlinks(FixedTimeslotTaskIF* thisSequence);
 
-ReturnValue_t pstAcs(FixedTimeslotTaskIF* thisSequence, AcsPstCfg cfg);
+ReturnValue_t pstTcsAndAcs(FixedTimeslotTaskIF* thisSequence, AcsPstCfg cfg);
 
 ReturnValue_t pstI2c(FixedTimeslotTaskIF* thisSequence);