diff --git a/CHANGELOG.md b/CHANGELOG.md
index 774d7d906..baa6e725f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,15 +10,30 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## Fixes
 
-- Linux OSAL `getUptime` fix: Check validity of `/proc/uptime` file before reading uptime.
 - PUS Health Service: Size check for set health command.
-- PUS Health Service: Perform operation completion for announce health command.
+                      Perform operation completion for announce health command.
+  https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/746
+- Linux OSAL `getUptime` fix: Check validity of `/proc/uptime` file before reading uptime.
+  https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/745
+- Small tweak for version getter
+  https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/744
 - PUS Scheduling Service: Use timeval internally
   PR: https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/735
 
-## Changed
+## Added
 
+- add CFDP subsystem ID
+  https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/742
+
+## Changed
+- Bump ETL version to 20.35.14
+  https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/748
+- Renamed `PCDU_2` subsystem ID to `POWER_SWITCH_IF`.
+  https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/743
+- Add new `PowerSwitchIF::SWITCH_UNKNOWN` returnvalue.
+  https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/743
 - Assert that `FixedArrayList` is larger than 0 at compile time.
+  https://egit.irs.uni-stuttgart.de/fsfw/fsfw/pulls/740
 
 # [v6.0.0] 2023-02-10
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5eddde7ff..5d35e6ff5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -72,7 +72,7 @@ set(FSFW_ETL_LIB_MAJOR_VERSION
     20
     CACHE STRING "ETL library major version requirement")
 set(FSFW_ETL_LIB_VERSION
-    ${FSFW_ETL_LIB_MAJOR_VERSION}.28.0
+    ${FSFW_ETL_LIB_MAJOR_VERSION}.35.14
     CACHE STRING "ETL library exact version requirement")
 set(FSFW_ETL_LINK_TARGET etl::etl)
 
diff --git a/src/fsfw/events/fwSubsystemIdRanges.h b/src/fsfw/events/fwSubsystemIdRanges.h
index 574ea0702..e395c2f96 100644
--- a/src/fsfw/events/fwSubsystemIdRanges.h
+++ b/src/fsfw/events/fwSubsystemIdRanges.h
@@ -10,7 +10,7 @@ enum : uint8_t {
   CDH = 28,
   TCS_1 = 59,
   PCDU_1 = 42,
-  PCDU_2 = 43,
+  POWER_SWITCH_IF = 43,
   HEATER = 50,
   T_SENSORS = 52,
   FDIR = 70,
diff --git a/src/fsfw/power/Fuse.h b/src/fsfw/power/Fuse.h
index e8b86cfde..c1b35899c 100644
--- a/src/fsfw/power/Fuse.h
+++ b/src/fsfw/power/Fuse.h
@@ -32,7 +32,7 @@ class Fuse : public SystemObject,
     gp_id_t poolIdPower;
   };
 
-  static const uint8_t SUBSYSTEM_ID = SUBSYSTEM_ID::PCDU_1;
+  static const uint8_t SUBSYSTEM_ID = SUBSYSTEM_ID::POWER_SWITCH_IF;
   //! PSS detected that current on a fuse is totally out of bounds.
   static const Event FUSE_CURRENT_HIGH = MAKE_EVENT(1, severity::LOW);
   //! PSS detected a fuse that went off.
diff --git a/src/fsfw/power/PowerSwitchIF.h b/src/fsfw/power/PowerSwitchIF.h
index e8c9aff4c..0b331e118 100644
--- a/src/fsfw/power/PowerSwitchIF.h
+++ b/src/fsfw/power/PowerSwitchIF.h
@@ -28,10 +28,12 @@ class PowerSwitchIF {
   static const ReturnValue_t SWITCH_TIMEOUT = MAKE_RETURN_CODE(2);
   static const ReturnValue_t FUSE_ON = MAKE_RETURN_CODE(3);
   static const ReturnValue_t FUSE_OFF = MAKE_RETURN_CODE(4);
-  static const uint8_t SUBSYSTEM_ID = SUBSYSTEM_ID::PCDU_2;
-  static const Event SWITCH_WENT_OFF = MAKE_EVENT(
-      0, severity::LOW);  //!< Someone detected that a switch went off which shouldn't. Severity:
-                          //!< Low, Parameter1: switchId1, Parameter2: switchId2
+  static const ReturnValue_t SWITCH_UNKNOWN = MAKE_RETURN_CODE(5);
+
+  static const uint8_t SUBSYSTEM_ID = SUBSYSTEM_ID::POWER_SWITCH_IF;
+  //!< Someone detected that a switch went off which shouldn't. Severity:
+  //!< Low, Parameter1: switchId1, Parameter2: switchId2
+  static const Event SWITCH_WENT_OFF = MAKE_EVENT(0, severity::LOW);
   /**
    * send a direct command to the Power Unit to enable/disable the specified switch.
    *
@@ -50,6 +52,7 @@ class PowerSwitchIF {
    * @return
    *     - @c SWITCH_ON if the specified switch is on.
    *     - @c SWITCH_OFF if the specified switch is off.
+   *     - @c SWITCH_UNKNOWN if the state of the specified switch is unknown.
    *     - @c returnvalue::FAILED if an error occured
    */
   virtual ReturnValue_t getSwitchState(power::Switch_t switchNr) const = 0;