diff --git a/src/modules/selector.cpp b/src/modules/selector.cpp
index 1bf2546..14b5251 100644
--- a/src/modules/selector.cpp
+++ b/src/modules/selector.cpp
@@ -65,6 +65,12 @@ Selector::OperationResult Selector::MoveToSlot(uint8_t slot) {
         return OperationResult::Accepted;
     }
 
+    if (mf::finda.Pressed()) {
+        // @@TODO not sure why (if) this happens, but anyway - we must not move the selector if FINDA is pressed
+        // That includes the CutFilament operation as well
+        return OperationResult::Refused;
+    }
+
     // coordinates invalid, first home, then engage
     if (!homingValid && mg::globals.FilamentLoaded() < mg::FilamentLoadState::InSelector) {
         PlanHome();
@@ -96,7 +102,7 @@ bool Selector::Step() {
         PerformHomeBack();
         return false;
     case Ready:
-        if (!homingValid && mg::globals.FilamentLoaded() < mg::InSelector) {
+        if (!homingValid && mg::globals.FilamentLoaded() < mg::InSelector && (!mf::finda.Pressed())) {
             PlanHome();
             return false;
         }
diff --git a/tests/unit/logic/cut_filament/test_cut_filament.cpp b/tests/unit/logic/cut_filament/test_cut_filament.cpp
index e938bff..5c42cc0 100644
--- a/tests/unit/logic/cut_filament/test_cut_filament.cpp
+++ b/tests/unit/logic/cut_filament/test_cut_filament.cpp
@@ -24,7 +24,7 @@ using Catch::Matchers::Equals;
 void CutSlot(logic::CutFilament &cf, uint8_t cutSlot) {
 
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     REQUIRE(VerifyEnvironmentState(mg::FilamentLoadState::AtPulley, mi::Idler::IdleSlotIndex(), 0, false, false, ml::off, ml::off));
 
diff --git a/tests/unit/logic/eject_filament/test_eject_filament.cpp b/tests/unit/logic/eject_filament/test_eject_filament.cpp
index 0ba4339..23bb494 100644
--- a/tests/unit/logic/eject_filament/test_eject_filament.cpp
+++ b/tests/unit/logic/eject_filament/test_eject_filament.cpp
@@ -26,7 +26,7 @@ TEST_CASE("eject_filament::eject0", "[eject_filament][.]") {
     using namespace logic;
 
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     EjectFilament ef;
     // restart the automaton
diff --git a/tests/unit/logic/failing_tmc/test_failing_tmc.cpp b/tests/unit/logic/failing_tmc/test_failing_tmc.cpp
index 1d80f72..c7bee44 100644
--- a/tests/unit/logic/failing_tmc/test_failing_tmc.cpp
+++ b/tests/unit/logic/failing_tmc/test_failing_tmc.cpp
@@ -40,7 +40,7 @@ void FailingMovableUnload(hal::tmc2130::ErrorFlags ef, ErrorCode ec, config::Axi
     ForceReinitAllAutomata();
 
     // change the startup to what we need here
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::InNozzle);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::InNozzle));
 
     // set FINDA ON + debounce
     SetFINDAStateAndDebounce(true);
@@ -90,7 +90,7 @@ void FailingMovableLoad(hal::tmc2130::ErrorFlags ef, ErrorCode ec, config::Axis
     ForceReinitAllAutomata();
 
     // change the startup to what we need here
-    EnsureActiveSlotIndex(5, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(5, mg::FilamentLoadState::AtPulley));
 
     // set FINDA OFF + debounce
     SetFINDAStateAndDebounce(false);
diff --git a/tests/unit/logic/feed_to_bondtech/test_feed_to_bondtech.cpp b/tests/unit/logic/feed_to_bondtech/test_feed_to_bondtech.cpp
index 65424ee..2053a8a 100644
--- a/tests/unit/logic/feed_to_bondtech/test_feed_to_bondtech.cpp
+++ b/tests/unit/logic/feed_to_bondtech/test_feed_to_bondtech.cpp
@@ -25,7 +25,7 @@ TEST_CASE("feed_to_bondtech::feed_phase_unlimited", "[feed_to_bondtech]") {
     using namespace logic;
 
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     FeedToBondtech fb;
     main_loop();
diff --git a/tests/unit/logic/feed_to_finda/test_feed_to_finda.cpp b/tests/unit/logic/feed_to_finda/test_feed_to_finda.cpp
index 014a427..f4fbe34 100644
--- a/tests/unit/logic/feed_to_finda/test_feed_to_finda.cpp
+++ b/tests/unit/logic/feed_to_finda/test_feed_to_finda.cpp
@@ -25,7 +25,7 @@ TEST_CASE("feed_to_finda::feed_phase_unlimited", "[feed_to_finda]") {
     using namespace logic;
 
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     FeedToFinda ff;
     main_loop();
@@ -93,7 +93,7 @@ TEST_CASE("feed_to_finda::FINDA_failed", "[feed_to_finda]") {
     using namespace logic;
 
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     FeedToFinda ff;
     main_loop();
diff --git a/tests/unit/logic/homing/test_homing.cpp b/tests/unit/logic/homing/test_homing.cpp
index 0dd3b9f..9a90101 100644
--- a/tests/unit/logic/homing/test_homing.cpp
+++ b/tests/unit/logic/homing/test_homing.cpp
@@ -29,7 +29,7 @@ bool SuccessfulHome(uint8_t slot) {
     ForceReinitAllAutomata();
 
     // change the startup to what we need here
-    EnsureActiveSlotIndex(slot, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(slot, mg::FilamentLoadState::AtPulley));
 
     // set FINDA OFF + debounce
     SetFINDAStateAndDebounce(false);
@@ -64,7 +64,7 @@ bool SelectorFailedRetry() {
     ForceReinitAllAutomata();
 
     // change the startup to what we need here
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     // set FINDA OFF + debounce
     SetFINDAStateAndDebounce(false);
@@ -95,3 +95,58 @@ bool SelectorFailedRetry() {
 TEST_CASE("homing::selector_failed_retry", "[homing]") {
     REQUIRE(SelectorFailedRetry());
 }
+
+bool RefusedMove(uint8_t slot) {
+    // prepare startup conditions
+    ForceReinitAllAutomata();
+
+    // change the startup to what we need here
+    HomeIdlerAndSelector();
+
+    SetFINDAStateAndDebounce(true);
+    mg::globals.SetFilamentLoaded(slot, mg::FilamentLoadState::InSelector);
+
+    // move selector to the right spot - should not be possible
+    REQUIRE(ms::selector.MoveToSlot(slot) == ms::Selector::OperationResult::Refused);
+    return true;
+}
+
+bool RefusedHome(uint8_t slot) {
+    // prepare startup conditions
+    ForceReinitAllAutomata();
+
+    // change the startup to what we need here
+    HomeIdlerAndSelector();
+
+    SetFINDAStateAndDebounce(true);
+    mg::globals.SetFilamentLoaded(slot, mg::FilamentLoadState::InSelector);
+
+    ms::selector.InvalidateHoming();
+
+    // selector should not start homing, because something is in the FINDA
+    for (uint8_t i = 0; i < 100; ++i) {
+        main_loop();
+        REQUIRE_FALSE(ms::selector.HomingValid());
+        REQUIRE(ms::selector.State() == ms::Selector::Ready);
+    }
+    // unpress FINDA
+    SetFINDAStateAndDebounce(false);
+    mg::globals.SetFilamentLoaded(slot, mg::FilamentLoadState::AtPulley);
+
+    // selector should start the homing sequence
+    main_loop();
+    REQUIRE(ms::selector.State() == ms::Selector::HomeForward);
+    return true;
+}
+
+TEST_CASE("homing::refused_move", "[homing]") {
+    for (uint8_t slot = 0; slot < config::toolCount; ++slot) {
+        REQUIRE(RefusedMove(slot));
+    }
+}
+
+TEST_CASE("homing::refused_home", "[homing]") {
+    for (uint8_t slot = 0; slot < config::toolCount; ++slot) {
+        REQUIRE(RefusedHome(slot));
+    }
+}
diff --git a/tests/unit/logic/load_filament/test_load_filament.cpp b/tests/unit/logic/load_filament/test_load_filament.cpp
index 8ad1750..a057043 100644
--- a/tests/unit/logic/load_filament/test_load_filament.cpp
+++ b/tests/unit/logic/load_filament/test_load_filament.cpp
@@ -28,7 +28,7 @@ void LoadFilamentCommonSetup(uint8_t slot, logic::LoadFilament &lf, bool feedLim
     ForceReinitAllAutomata();
 
     // change the startup to what we need here
-    EnsureActiveSlotIndex(slot, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(slot, mg::FilamentLoadState::AtPulley));
 
     // verify startup conditions
     REQUIRE(VerifyState(lf, mg::FilamentLoadState::AtPulley, mi::Idler::IdleSlotIndex(), slot, false, false, ml::off, ml::off, ErrorCode::OK, ProgressCode::OK));
@@ -375,8 +375,8 @@ TEST_CASE("load_filament::avoid_load_filament_finda", "[load_filament]") {
         for (uint8_t activeSlot = 0; activeSlot < config::toolCount; ++activeSlot) {
             logic::LoadFilament lf;
             ForceReinitAllAutomata();
-            SetFINDAStateAndDebounce(true);
-            EnsureActiveSlotIndex(activeSlot, fls);
+            REQUIRE(EnsureActiveSlotIndex(activeSlot, fls));
+            SetFINDAStateAndDebounce(true); // beware - selector will refuse to move if FINDA is pressed - must set active slot first and then FINDA
             REQUIRE(VerifyState(lf, fls, mi::Idler::IdleSlotIndex(), activeSlot, true, false, ml::off, ml::off, ErrorCode::OK, ProgressCode::OK));
             bool accepted = lf.Reset(slot);
             if (activeSlot != slot) {
diff --git a/tests/unit/logic/stubs/main_loop_stub.cpp b/tests/unit/logic/stubs/main_loop_stub.cpp
index cc27513..9ca7bb5 100644
--- a/tests/unit/logic/stubs/main_loop_stub.cpp
+++ b/tests/unit/logic/stubs/main_loop_stub.cpp
@@ -84,16 +84,18 @@ void HomeIdlerAndSelector() {
     SimulateIdlerAndSelectorHoming(nc);
 }
 
-void EnsureActiveSlotIndex(uint8_t slot, mg::FilamentLoadState loadState) {
+bool EnsureActiveSlotIndex(uint8_t slot, mg::FilamentLoadState loadState) {
     HomeIdlerAndSelector();
 
     // move selector to the right spot
-    ms::selector.MoveToSlot(slot);
+    if (ms::selector.MoveToSlot(slot) == ms::Selector::OperationResult::Refused)
+        return false;
     while (ms::selector.Slot() != slot)
         main_loop();
 
     // mg::globals.SetActiveSlot(slot);
     mg::globals.SetFilamentLoaded(slot, loadState);
+    return true;
 }
 
 void SetFINDAStateAndDebounce(bool press) {
diff --git a/tests/unit/logic/stubs/main_loop_stub.h b/tests/unit/logic/stubs/main_loop_stub.h
index b3fad03..beab977 100644
--- a/tests/unit/logic/stubs/main_loop_stub.h
+++ b/tests/unit/logic/stubs/main_loop_stub.h
@@ -22,7 +22,7 @@ bool WhileTopState(SM &sm, ProgressCode state, uint32_t maxLoops = 5000) {
         sm, [&](uint32_t) { return sm.TopLevelState() == state; }, maxLoops);
 }
 
-void EnsureActiveSlotIndex(uint8_t slot, modules::globals::FilamentLoadState loadState);
+bool EnsureActiveSlotIndex(uint8_t slot, modules::globals::FilamentLoadState loadState);
 
 void SetFINDAStateAndDebounce(bool press);
 bool SimulateUnloadToFINDA(uint32_t step, uint32_t fsOff, uint32_t findaOff);
@@ -37,3 +37,5 @@ void ClearButtons(logic::CommandBase &cb);
 // ... could be computed in the future from the pre-set number of microsteps and real positions
 static constexpr uint32_t idlerEngageDisengageMaxSteps = 40000UL;
 static constexpr uint32_t selectorMoveMaxSteps = 40000UL;
+
+void HomeIdlerAndSelector();
diff --git a/tests/unit/logic/tool_change/test_tool_change.cpp b/tests/unit/logic/tool_change/test_tool_change.cpp
index 421af33..25960d3 100644
--- a/tests/unit/logic/tool_change/test_tool_change.cpp
+++ b/tests/unit/logic/tool_change/test_tool_change.cpp
@@ -65,9 +65,9 @@ void CheckFinishedCorrectly(logic::ToolChange &tc, uint8_t toSlot) {
 void ToolChange(logic::ToolChange &tc, uint8_t fromSlot, uint8_t toSlot) {
     ForceReinitAllAutomata();
 
+    REQUIRE(EnsureActiveSlotIndex(fromSlot, mg::FilamentLoadState::InNozzle));
     SetFINDAStateAndDebounce(true);
     mfs::fsensor.ProcessMessage(true);
-    EnsureActiveSlotIndex(fromSlot, mg::FilamentLoadState::InNozzle);
 
     // restart the automaton
     tc.Reset(toSlot);
@@ -96,10 +96,10 @@ void ToolChange(logic::ToolChange &tc, uint8_t fromSlot, uint8_t toSlot) {
 void NoToolChange(logic::ToolChange &tc, uint8_t fromSlot, uint8_t toSlot) {
     ForceReinitAllAutomata();
 
+    REQUIRE(EnsureActiveSlotIndex(fromSlot, mg::FilamentLoadState::InNozzle));
     // the filament is LOADED
-    SetFINDAStateAndDebounce(true);
     mfs::fsensor.ProcessMessage(true);
-    EnsureActiveSlotIndex(fromSlot, mg::FilamentLoadState::InNozzle);
+    SetFINDAStateAndDebounce(true);
 
     REQUIRE(VerifyEnvironmentState(mg::FilamentLoadState::InNozzle, mi::Idler::IdleSlotIndex(), toSlot, true, false, ml::off, ml::off));
 
@@ -114,7 +114,7 @@ void NoToolChange(logic::ToolChange &tc, uint8_t fromSlot, uint8_t toSlot) {
 void JustLoadFilament(logic::ToolChange &tc, uint8_t slot) {
     ForceReinitAllAutomata();
 
-    EnsureActiveSlotIndex(slot, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(slot, mg::FilamentLoadState::AtPulley));
 
     // verify filament NOT loaded
     REQUIRE(VerifyEnvironmentState(mg::FilamentLoadState::AtPulley, mi::Idler::IdleSlotIndex(), slot, false, false, ml::off, ml::off));
@@ -175,9 +175,9 @@ TEST_CASE("tool_change::same_slot_just_unloaded_filament", "[tool_change]") {
 void ToolChangeFailLoadToFinda(logic::ToolChange &tc, uint8_t fromSlot, uint8_t toSlot) {
     ForceReinitAllAutomata();
 
+    REQUIRE(EnsureActiveSlotIndex(fromSlot, mg::FilamentLoadState::InNozzle));
     SetFINDAStateAndDebounce(true);
     mfs::fsensor.ProcessMessage(true);
-    EnsureActiveSlotIndex(fromSlot, mg::FilamentLoadState::InNozzle);
 
     // restart the automaton
     tc.Reset(toSlot);
@@ -330,9 +330,9 @@ void ToolChangeFailFSensor(logic::ToolChange &tc, uint8_t fromSlot, uint8_t toSl
     using namespace std::placeholders;
     ForceReinitAllAutomata();
 
+    REQUIRE(EnsureActiveSlotIndex(fromSlot, mg::FilamentLoadState::InNozzle));
     SetFINDAStateAndDebounce(true);
     mfs::fsensor.ProcessMessage(true);
-    EnsureActiveSlotIndex(fromSlot, mg::FilamentLoadState::InNozzle);
 
     // restart the automaton
     tc.Reset(toSlot);
diff --git a/tests/unit/logic/unload_filament/test_unload_filament.cpp b/tests/unit/logic/unload_filament/test_unload_filament.cpp
index e9b17a8..bbd66a4 100644
--- a/tests/unit/logic/unload_filament/test_unload_filament.cpp
+++ b/tests/unit/logic/unload_filament/test_unload_filament.cpp
@@ -28,7 +28,7 @@ void RegularUnloadFromSlot04Init(uint8_t slot, logic::UnloadFilament &uf) {
     ForceReinitAllAutomata();
 
     // change the startup to what we need here
-    EnsureActiveSlotIndex(slot, mg::FilamentLoadState::InNozzle);
+    REQUIRE(EnsureActiveSlotIndex(slot, mg::FilamentLoadState::InNozzle));
 
     // set FINDA ON + debounce
     SetFINDAStateAndDebounce(true);
@@ -108,7 +108,7 @@ void FindaDidntTriggerCommonSetup(uint8_t slot, logic::UnloadFilament &uf) {
 
     // change the startup to what we need here
     // move selector to the right spot
-    EnsureActiveSlotIndex(slot, mg::FilamentLoadState::InNozzle);
+    REQUIRE(EnsureActiveSlotIndex(slot, mg::FilamentLoadState::InNozzle));
 
     // set FINDA ON + debounce
     SetFINDAStateAndDebounce(true);
@@ -279,7 +279,7 @@ TEST_CASE("unload_filament::not_loaded", "[unload_filament]") {
 
     // change the startup to what we need here
     // move selector to the right spot
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     // verify startup conditions
     REQUIRE(VerifyState(uf, mg::FilamentLoadState::AtPulley, mi::Idler::IdleSlotIndex(), 0, false, false, ml::off, ml::off, ErrorCode::OK, ProgressCode::OK));
diff --git a/tests/unit/logic/unload_to_finda/test_unload_to_finda.cpp b/tests/unit/logic/unload_to_finda/test_unload_to_finda.cpp
index b68c29e..e55f5ea 100644
--- a/tests/unit/logic/unload_to_finda/test_unload_to_finda.cpp
+++ b/tests/unit/logic/unload_to_finda/test_unload_to_finda.cpp
@@ -26,7 +26,7 @@ namespace ha = hal::adc;
 
 TEST_CASE("unload_to_finda::regular_unload", "[unload_to_finda]") {
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     // we need finda ON
     SetFINDAStateAndDebounce(true);
@@ -64,7 +64,7 @@ TEST_CASE("unload_to_finda::regular_unload", "[unload_to_finda]") {
 
 TEST_CASE("unload_to_finda::no_sense_FINDA_upon_start", "[unload_to_finda]") {
     ForceReinitAllAutomata(); // that implies FINDA OFF which should really not happen for an unload call
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     logic::UnloadToFinda ff;
 
@@ -78,7 +78,7 @@ TEST_CASE("unload_to_finda::no_sense_FINDA_upon_start", "[unload_to_finda]") {
 
 TEST_CASE("unload_to_finda::unload_without_FINDA_trigger", "[unload_to_finda]") {
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     // we need finda ON
     SetFINDAStateAndDebounce(true);
@@ -119,7 +119,7 @@ TEST_CASE("unload_to_finda::unload_without_FINDA_trigger", "[unload_to_finda]")
 
 TEST_CASE("unload_to_finda::unload_without_FSensor_trigger", "[unload_to_finda]") {
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     // we need finda ON
     SetFINDAStateAndDebounce(true);
@@ -160,7 +160,7 @@ TEST_CASE("unload_to_finda::unload_without_FSensor_trigger", "[unload_to_finda]"
 
 TEST_CASE("unload_to_finda::unload_repeated", "[unload_to_finda]") {
     ForceReinitAllAutomata();
-    EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley);
+    REQUIRE(EnsureActiveSlotIndex(0, mg::FilamentLoadState::AtPulley));
 
     // we need finda ON
     SetFINDAStateAndDebounce(true);