diff --git a/api/src/opentrons/protocol_engine/state/addressable_areas.py b/api/src/opentrons/protocol_engine/state/addressable_areas.py
index c1857ee6dde..bbad97db7b5 100644
--- a/api/src/opentrons/protocol_engine/state/addressable_areas.py
+++ b/api/src/opentrons/protocol_engine/state/addressable_areas.py
@@ -211,9 +211,9 @@ def _add_addressable_area(self, addressable_area_name: str) -> None:
                     deck_definition=self._state.deck_definition,
                 )
             )
-            self._state.loaded_addressable_areas_by_name[addressable_area.area_name] = (
-                addressable_area
-            )
+            self._state.loaded_addressable_areas_by_name[
+                addressable_area.area_name
+            ] = addressable_area
 
     def _validate_addressable_area_for_simulation(
         self, addressable_area_name: str
@@ -236,9 +236,9 @@ def _validate_addressable_area_for_simulation(
                 set(potential_fixtures)
             )
 
-            self._state.potential_cutout_fixtures_by_cutout_id[cutout_id] = (
-                remaining_fixtures
-            )
+            self._state.potential_cutout_fixtures_by_cutout_id[
+                cutout_id
+            ] = remaining_fixtures
         else:
             self._state.potential_cutout_fixtures_by_cutout_id[cutout_id] = set(
                 potential_fixtures
diff --git a/api/tests/opentrons/protocol_engine/state/test_geometry_view.py b/api/tests/opentrons/protocol_engine/state/test_geometry_view.py
index 948347ce4f4..81f35b41183 100644
--- a/api/tests/opentrons/protocol_engine/state/test_geometry_view.py
+++ b/api/tests/opentrons/protocol_engine/state/test_geometry_view.py
@@ -76,7 +76,6 @@
     OnLabwareLocationSequenceComponent,
     NotOnDeckLocationSequenceComponent,
     OnCutoutFixtureLocationSequenceComponent,
-    PotentialCutoutFixture,
 )
 from opentrons.protocol_engine.commands import (
     CommandStatus,
diff --git a/robot-server/tests/integration/http_api/protocols/test_v6_json_upload.tavern.yaml b/robot-server/tests/integration/http_api/protocols/test_v6_json_upload.tavern.yaml
index e6a76463763..6b6de70fb72 100644
--- a/robot-server/tests/integration/http_api/protocols/test_v6_json_upload.tavern.yaml
+++ b/robot-server/tests/integration/http_api/protocols/test_v6_json_upload.tavern.yaml
@@ -212,7 +212,10 @@ stages:
                       moduleId: temperatureModuleId
                     - kind: onAddressableArea
                       addressableAreaName: '1'
-                      slotName: '1'
+                    - kind: onCutoutFixture
+                      cutoutId: cutout1
+                      possibleCutoutFixtureIds:
+                        - 'singleStandardSlot'
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
@@ -237,7 +240,10 @@ stages:
                       moduleId: magneticModuleId
                     - kind: onAddressableArea
                       addressableAreaName: '3'
-                      slotName: '3'
+                    - kind: onCutoutFixture
+                      cutoutId: cutout3
+                      possibleCutoutFixtureIds:
+                        - 'singleStandardSlot'
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
@@ -260,7 +266,10 @@ stages:
                   locationSequence:
                     - kind: onAddressableArea
                       addressableAreaName: '8'
-                      slotName: '8'
+                    - kind: onCutoutFixture
+                      cutoutId: cutout8
+                      possibleCutoutFixtureIds:
+                        - 'singleStandardSlot'
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
diff --git a/robot-server/tests/integration/http_api/protocols/test_v8_json_upload_flex.tavern.yaml b/robot-server/tests/integration/http_api/protocols/test_v8_json_upload_flex.tavern.yaml
index d77fa75c60f..c3afd71907e 100644
--- a/robot-server/tests/integration/http_api/protocols/test_v8_json_upload_flex.tavern.yaml
+++ b/robot-server/tests/integration/http_api/protocols/test_v8_json_upload_flex.tavern.yaml
@@ -219,11 +219,19 @@ stages:
                   labwareId: sourcePlateId
                   definition: !anydict
                   locationSequence:
-                    - kind: onModule
-                      moduleId: temperatureModuleId
                     - kind: onAddressableArea
                       addressableAreaName: temperatureModuleV2D1
-                      slotName: D1
+                    - kind: onModule
+                      moduleId: temperatureModuleId
+                    - kind: onCutoutFixture
+                      cutoutId: cutoutD1
+                      # note: this is not how it should work and happens because the loadModule
+                      # command always loads onto an addressable area, presenting a conflict between
+                      # the cutout fixture required by the module being present and the cutout fixture
+                      # required by the deck slot addressable area that was used to load the module
+                      # being present. other work will fix this, and once that other work is merged
+                      # this value should be ["temperatureModuleV2"]
+                      possibleCutoutFixtureIds: []
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
@@ -244,11 +252,14 @@ stages:
                   labwareId: destPlateId
                   definition: !anydict
                   locationSequence:
-                    - kind: onModule
-                      moduleId: magneticBlockId
                     - kind: onAddressableArea
                       addressableAreaName: magneticBlockV1D3
-                      slotName: D3
+                    - kind: onModule
+                      moduleId: magneticBlockId
+                    - kind: onCutoutFixture
+                      cutoutId: cutoutD3
+                      # note: this should be ["magneticBlockV1"], see above
+                      possibleCutoutFixtureIds: []
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
@@ -271,7 +282,10 @@ stages:
                   locationSequence:
                     - kind: onAddressableArea
                       addressableAreaName: B2
-                      slotName: B2
+                    - kind: onCutoutFixture
+                      cutoutId: cutoutB2
+                      possibleCutoutFixtureIds:
+                        - singleCenterSlot
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
@@ -294,7 +308,12 @@ stages:
                   locationSequence:
                     - kind: onAddressableArea
                       addressableAreaName: A3
-                      slotName: A3
+                    - kind: onCutoutFixture
+                      cutoutId: cutoutA3
+                      possibleCutoutFixtureIds:
+                        - flexStackerModuleV1
+                        - singleRightSlot
+                        - stagingAreaRightSlot
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
diff --git a/robot-server/tests/integration/http_api/protocols/test_v8_json_upload_ot2.tavern.yaml b/robot-server/tests/integration/http_api/protocols/test_v8_json_upload_ot2.tavern.yaml
index d27ff1a7e4e..a4e20528280 100644
--- a/robot-server/tests/integration/http_api/protocols/test_v8_json_upload_ot2.tavern.yaml
+++ b/robot-server/tests/integration/http_api/protocols/test_v8_json_upload_ot2.tavern.yaml
@@ -223,7 +223,10 @@ stages:
                       moduleId: temperatureModuleId
                     - kind: onAddressableArea
                       addressableAreaName: '1'
-                      slotName: '1'
+                    - kind: onCutoutFixture
+                      cutoutId: cutout1
+                      possibleCutoutFixtureIds:
+                        - singleStandardSlot
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
@@ -248,7 +251,10 @@ stages:
                       moduleId: magneticModuleId
                     - kind: onAddressableArea
                       addressableAreaName: '3'
-                      slotName: '3'
+                    - kind: onCutoutFixture
+                      cutoutId: cutout3
+                      possibleCutoutFixtureIds:
+                        - singleStandardSlot
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
@@ -271,7 +277,10 @@ stages:
                   locationSequence:
                     - kind: onAddressableArea
                       addressableAreaName: '8'
-                      slotName: '8'
+                    - kind: onCutoutFixture
+                      cutoutId: cutout8
+                      possibleCutoutFixtureIds:
+                        - singleStandardSlot
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
@@ -294,7 +303,10 @@ stages:
                   locationSequence:
                     - kind: onAddressableArea
                       addressableAreaName: '12'
-                      slotName: '12'
+                    - kind: onCutoutFixture
+                      cutoutId: cutout12
+                      possibleCutoutFixtureIds:
+                        - singleStandardSlot
                 notes: []
                 startedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"
                 completedAt: !re_fullmatch "\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d+(Z|([+-]\\d{2}:\\d{2}))"