diff --git a/src/sfizz/Region.cpp b/src/sfizz/Region.cpp
index f4be5582..d7826720 100644
--- a/src/sfizz/Region.cpp
+++ b/src/sfizz/Region.cpp
@@ -296,21 +296,21 @@ bool sfz::Region::parseOpcode(const Opcode& rawOpcode)
     case hash("sw_hikey"):
         break;
     case hash("sw_last"):
-        setValueFromOpcode(opcode, keyswitch, Default::keyRange);
+        setValueFromOpcode(opcode, lastKeyswitch, Default::keyRange);
         keySwitched = false;
         break;
     case hash("sw_label"):
         keyswitchLabel = opcode.value;
         break;
     case hash("sw_down"):
-        setValueFromOpcode(opcode, keyswitchDown, Default::keyRange);
+        setValueFromOpcode(opcode, downKeyswitch, Default::keyRange);
         keySwitched = false;
         break;
     case hash("sw_up"):
-        setValueFromOpcode(opcode, keyswitchUp, Default::keyRange);
+        setValueFromOpcode(opcode, upKeyswitch, Default::keyRange);
         break;
     case hash("sw_previous"):
-        setValueFromOpcode(opcode, previousNote, Default::keyRange);
+        setValueFromOpcode(opcode, previousKeyswitch, Default::keyRange);
         previousKeySwitched = false;
         break;
     case hash("sw_vel"):
@@ -1844,14 +1844,14 @@ void sfz::Region::offsetAllKeys(int offset) noexcept
     pitchKeycenter = offsetAndClampKey(pitchKeycenter, offset, Default::keyRange);
 
     // Offset key switches
-    if (keyswitchUp)
-        keyswitchUp = offsetAndClampKey(*keyswitchUp, offset, Default::keyRange);
-    if (keyswitch)
-        keyswitch = offsetAndClampKey(*keyswitch, offset, Default::keyRange);
-    if (keyswitchDown)
-        keyswitchDown = offsetAndClampKey(*keyswitchDown, offset, Default::keyRange);
-    if (previousNote)
-        previousNote = offsetAndClampKey(*previousNote, offset, Default::keyRange);
+    if (upKeyswitch)
+        upKeyswitch = offsetAndClampKey(*upKeyswitch, offset, Default::keyRange);
+    if (lastKeyswitch)
+        lastKeyswitch = offsetAndClampKey(*lastKeyswitch, offset, Default::keyRange);
+    if (downKeyswitch)
+        downKeyswitch = offsetAndClampKey(*downKeyswitch, offset, Default::keyRange);
+    if (previousKeyswitch)
+        previousKeyswitch = offsetAndClampKey(*previousKeyswitch, offset, Default::keyRange);
 
     // Offset crossfade ranges
     if (crossfadeKeyInRange != Default::crossfadeKeyInRange) {
diff --git a/src/sfizz/Region.h b/src/sfizz/Region.h
index a88ab965..996eec4e 100644
--- a/src/sfizz/Region.h
+++ b/src/sfizz/Region.h
@@ -347,11 +347,11 @@ struct Region {
     // Region logic: MIDI conditions
     Range<float> bendRange { Default::bendValueRange }; // hibend and lobend
     CCMap<Range<float>> ccConditions { Default::ccValueRange };
-    absl::optional<uint8_t> keyswitch {}; // sw_last
+    absl::optional<uint8_t> lastKeyswitch {}; // sw_last
     absl::optional<std::string> keyswitchLabel {};
-    absl::optional<uint8_t> keyswitchUp {}; // sw_up
-    absl::optional<uint8_t> keyswitchDown {}; // sw_down
-    absl::optional<uint8_t> previousNote {}; // sw_previous
+    absl::optional<uint8_t> upKeyswitch {}; // sw_up
+    absl::optional<uint8_t> downKeyswitch {}; // sw_down
+    absl::optional<uint8_t> previousKeyswitch {}; // sw_previous
     SfzVelocityOverride velocityOverride { Default::velocityOverride }; // sw_vel
     bool checkSustain { Default::checkSustain }; // sustain_sw
     bool checkSostenuto { Default::checkSostenuto }; // sostenuto_sw
diff --git a/src/sfizz/Synth.cpp b/src/sfizz/Synth.cpp
index 143e22ba..631a5b43 100644
--- a/src/sfizz/Synth.cpp
+++ b/src/sfizz/Synth.cpp
@@ -175,16 +175,16 @@ void sfz::Synth::buildRegion(const std::vector<Opcode>& regionOpcodes)
     if (octaveOffset != 0 || noteOffset != 0)
         lastRegion->offsetAllKeys(octaveOffset * 12 + noteOffset);
 
-    if (lastRegion->keyswitch)
-        lastKeyswitchLists[*lastRegion->keyswitch].push_back(lastRegion.get());
+    if (lastRegion->lastKeyswitch)
+        lastKeyswitchLists[*lastRegion->lastKeyswitch].push_back(lastRegion.get());
 
-    if (lastRegion->keyswitchUp)
-        upKeyswitchLists[*lastRegion->keyswitchUp].push_back(lastRegion.get());
+    if (lastRegion->upKeyswitch)
+        upKeyswitchLists[*lastRegion->upKeyswitch].push_back(lastRegion.get());
 
-    if (lastRegion->keyswitchDown)
-        downKeyswitchLists[*lastRegion->keyswitchDown].push_back(lastRegion.get());
+    if (lastRegion->downKeyswitch)
+        downKeyswitchLists[*lastRegion->downKeyswitch].push_back(lastRegion.get());
 
-    if (lastRegion->previousNote)
+    if (lastRegion->previousKeyswitch)
         previousKeyswitchLists.push_back(lastRegion.get());
 
     // There was a combination of group= and polyphony= on a region, so set the group polyphony
@@ -614,12 +614,12 @@ void sfz::Synth::finalizeSfzLoad()
             }
         }
 
-        if (region->keyswitch) {
+        if (region->lastKeyswitch) {
             if (currentSwitch)
-                region->keySwitched = (*currentSwitch == *region->keyswitch);
+                region->keySwitched = (*currentSwitch == *region->lastKeyswitch);
 
             if (region->keyswitchLabel)
-                insertPairUniquely(keyswitchLabels, *region->keyswitch, *region->keyswitchLabel);
+                insertPairUniquely(keyswitchLabels, *region->lastKeyswitch, *region->keyswitchLabel);
         }
 
         // Some regions had group number but no "group-level" opcodes handled the polyphony
@@ -1184,7 +1184,7 @@ void sfz::Synth::noteOnDispatch(int delay, int noteNumber, float velocity) noexc
     }
 
     for (auto& region : previousKeyswitchLists)
-        region->previousKeySwitched = (*region->previousNote == noteNumber);
+        region->previousKeySwitched = (*region->previousKeyswitch == noteNumber);
 }
 
 void sfz::Synth::startDelayedReleaseVoices(Region* region, int delay, SisterVoiceRingBuilder& ring) noexcept
diff --git a/tests/FilesT.cpp b/tests/FilesT.cpp
index 8917e591..b0a19757 100644
--- a/tests/FilesT.cpp
+++ b/tests/FilesT.cpp
@@ -463,14 +463,14 @@ TEST_CASE("[Files] Note and octave offsets")
     REQUIRE(synth.getRegionView(2)->crossfadeKeyOutRange == Range<uint8_t>(45, 49));
 
     REQUIRE(synth.getRegionView(3)->keyRange == Range<uint8_t>(62, 62));
-    REQUIRE( synth.getRegionView(3)->keyswitch );
-    REQUIRE( *synth.getRegionView(3)->keyswitch == 24 );
-    REQUIRE( synth.getRegionView(3)->keyswitchUp );
-    REQUIRE( *synth.getRegionView(3)->keyswitchUp == 24 );
-    REQUIRE( synth.getRegionView(3)->keyswitchDown );
-    REQUIRE( *synth.getRegionView(3)->keyswitchDown == 24 );
-    REQUIRE( synth.getRegionView(3)->previousNote );
-    REQUIRE( *synth.getRegionView(3)->previousNote == 61 );
+    REQUIRE( synth.getRegionView(3)->lastKeyswitch );
+    REQUIRE( *synth.getRegionView(3)->lastKeyswitch == 24 );
+    REQUIRE( synth.getRegionView(3)->upKeyswitch );
+    REQUIRE( *synth.getRegionView(3)->upKeyswitch == 24 );
+    REQUIRE( synth.getRegionView(3)->downKeyswitch );
+    REQUIRE( *synth.getRegionView(3)->downKeyswitch == 24 );
+    REQUIRE( synth.getRegionView(3)->previousKeyswitch );
+    REQUIRE( *synth.getRegionView(3)->previousKeyswitch == 61 );
 
     REQUIRE(synth.getRegionView(4)->keyRange == Range<uint8_t>(76, 76));
     REQUIRE( synth.getRegionView(4)->pitchKeycenter == 76 );
diff --git a/tests/RegionActivationT.cpp b/tests/RegionActivationT.cpp
index 7a08ce76..0763b56f 100644
--- a/tests/RegionActivationT.cpp
+++ b/tests/RegionActivationT.cpp
@@ -177,7 +177,7 @@ TEST_CASE("Region activation", "Region tests")
     }
 }
 
-TEST_CASE("[Keyswitches] Normal keyswitch range")
+TEST_CASE("[Keyswitches] Normal lastKeyswitch range")
 {
     sfz::Synth synth;
     synth.loadSfzString(fs::current_path() / "tests/TestFiles/keyswitches.sfz", R"(
@@ -196,7 +196,7 @@ TEST_CASE("[Keyswitches] Normal keyswitch range")
     REQUIRE(synth.getNumActiveVoices(true) == 2);
 }
 
-TEST_CASE("[Keyswitches] No keyswitch range")
+TEST_CASE("[Keyswitches] No lastKeyswitch range")
 {
     sfz::Synth synth;
     synth.loadSfzString(fs::current_path() / "tests/TestFiles/keyswitches.sfz", R"(
@@ -219,7 +219,7 @@ TEST_CASE("[Keyswitches] No keyswitch range")
     REQUIRE(synth.getNumActiveVoices(true) == 2);
 }
 
-TEST_CASE("[Keyswitches] Out of keyswitch range")
+TEST_CASE("[Keyswitches] Out of lastKeyswitch range")
 {
     sfz::Synth synth;
     synth.loadSfzString(fs::current_path() / "tests/TestFiles/keyswitches.sfz", R"(
@@ -238,7 +238,7 @@ TEST_CASE("[Keyswitches] Out of keyswitch range")
     REQUIRE(synth.getNumActiveVoices(true) == 2);
 }
 
-TEST_CASE("[Keyswitches] Overlapping key and keyswitch range")
+TEST_CASE("[Keyswitches] Overlapping key and lastKeyswitch range")
 {
     sfz::Synth synth;
     synth.loadSfzString(fs::current_path() / "tests/TestFiles/keyswitches.sfz", R"(
diff --git a/tests/RegionT.cpp b/tests/RegionT.cpp
index 2b1cc780..7e20583c 100644
--- a/tests/RegionT.cpp
+++ b/tests/RegionT.cpp
@@ -350,58 +350,58 @@ TEST_CASE("[Region] Parsing opcodes")
 
     SECTION("sw_last")
     {
-        REQUIRE(!region.keyswitch);
+        REQUIRE(!region.lastKeyswitch);
         region.parseOpcode({ "sw_last", "4" });
-        REQUIRE(region.keyswitch);
-        REQUIRE(*region.keyswitch == 4);
+        REQUIRE(region.lastKeyswitch);
+        REQUIRE(*region.lastKeyswitch == 4);
         region.parseOpcode({ "sw_last", "128" });
-        REQUIRE(region.keyswitch);
-        REQUIRE(*region.keyswitch == 127);
+        REQUIRE(region.lastKeyswitch);
+        REQUIRE(*region.lastKeyswitch == 127);
         region.parseOpcode({ "sw_last", "-1" });
-        REQUIRE(region.keyswitch);
-        REQUIRE(*region.keyswitch == 0);
+        REQUIRE(region.lastKeyswitch);
+        REQUIRE(*region.lastKeyswitch == 0);
     }
 
     SECTION("sw_up")
     {
-        REQUIRE(!region.keyswitchUp);
+        REQUIRE(!region.upKeyswitch);
         region.parseOpcode({ "sw_up", "4" });
-        REQUIRE(region.keyswitchUp);
-        REQUIRE(*region.keyswitchUp == 4);
+        REQUIRE(region.upKeyswitch);
+        REQUIRE(*region.upKeyswitch == 4);
         region.parseOpcode({ "sw_up", "128" });
-        REQUIRE(region.keyswitchUp);
-        REQUIRE(*region.keyswitchUp == 127);
+        REQUIRE(region.upKeyswitch);
+        REQUIRE(*region.upKeyswitch == 127);
         region.parseOpcode({ "sw_up", "-1" });
-        REQUIRE(region.keyswitchUp);
-        REQUIRE(*region.keyswitchUp == 0);
+        REQUIRE(region.upKeyswitch);
+        REQUIRE(*region.upKeyswitch == 0);
     }
 
     SECTION("sw_down")
     {
-        REQUIRE(!region.keyswitchDown);
+        REQUIRE(!region.downKeyswitch);
         region.parseOpcode({ "sw_down", "4" });
-        REQUIRE(region.keyswitchDown);
-        REQUIRE(*region.keyswitchDown == 4);
+        REQUIRE(region.downKeyswitch);
+        REQUIRE(*region.downKeyswitch == 4);
         region.parseOpcode({ "sw_down", "128" });
-        REQUIRE(region.keyswitchDown);
-        REQUIRE(*region.keyswitchDown == 127);
+        REQUIRE(region.downKeyswitch);
+        REQUIRE(*region.downKeyswitch == 127);
         region.parseOpcode({ "sw_down", "-1" });
-        REQUIRE(region.keyswitchDown);
-        REQUIRE(*region.keyswitchDown == 0);
+        REQUIRE(region.downKeyswitch);
+        REQUIRE(*region.downKeyswitch == 0);
     }
 
     SECTION("sw_previous")
     {
-        REQUIRE(!region.previousNote);
+        REQUIRE(!region.previousKeyswitch);
         region.parseOpcode({ "sw_previous", "4" });
-        REQUIRE(region.previousNote);
-        REQUIRE(*region.previousNote == 4);
+        REQUIRE(region.previousKeyswitch);
+        REQUIRE(*region.previousKeyswitch == 4);
         region.parseOpcode({ "sw_previous", "128" });
-        REQUIRE(region.previousNote);
-        REQUIRE(*region.previousNote == 127);
+        REQUIRE(region.previousKeyswitch);
+        REQUIRE(*region.previousKeyswitch == 127);
         region.parseOpcode({ "sw_previous", "-1" });
-        REQUIRE(region.previousNote);
-        REQUIRE(*region.previousNote == 0);
+        REQUIRE(region.previousKeyswitch);
+        REQUIRE(*region.previousKeyswitch == 0);
     }
 
     SECTION("sw_vel")