diff --git a/README.md b/README.md
index 913c1fe55..9556fd8b3 100644
--- a/README.md
+++ b/README.md
@@ -45,7 +45,7 @@ The first time it will also set up your pre-commit hooks.
 
 We use [Proxygen](https://github.com/NHSDigital/proxygen-cli) to deploy our proxies and specs to APIM which we have wrapped up into a make command:
 
-- `make apigee-deploy`
+- `make apigee--deploy`
 
 This when run locally will need you to have done a local `terraform--plan` and `terraform--apply` (as it will read some details from the output files)
 
diff --git a/src/etl/sds/worker/load/tests/test_load_worker.py b/src/etl/sds/worker/load/tests/test_load_worker.py
index 140e1cf0c..9d5a150b0 100644
--- a/src/etl/sds/worker/load/tests/test_load_worker.py
+++ b/src/etl/sds/worker/load/tests/test_load_worker.py
@@ -1,5 +1,6 @@
 import os
 from collections import deque
+from datetime import datetime
 from itertools import chain, permutations
 from typing import Callable, Generator
 from unittest import mock
@@ -33,6 +34,9 @@
         "product_team_id": str(UUID(int=1)),
         "ods_code": "ABC",
         "status": "active",
+        "created_on": datetime.utcnow(),
+        "updated_on": None,
+        "deleted_on": None,
     }
 }
 GOOD_CPM_EVENT_2 = {
@@ -43,6 +47,9 @@
         "product_team_id": str(UUID(int=2)),
         "ods_code": "ABC",
         "status": "active",
+        "created_on": datetime.utcnow(),
+        "updated_on": None,
+        "deleted_on": None,
     }
 }
 
diff --git a/src/layers/domain/core/device.py b/src/layers/domain/core/device.py
index 09b915b72..bd331942a 100644
--- a/src/layers/domain/core/device.py
+++ b/src/layers/domain/core/device.py
@@ -1,6 +1,8 @@
 from collections import defaultdict
+from datetime import datetime
 from enum import StrEnum, auto
 from itertools import chain
+from typing import Optional
 from uuid import UUID, uuid4
 
 from attr import dataclass, field
@@ -40,6 +42,9 @@ class DeviceCreatedEvent(Event):
     product_team_id: UUID
     ods_code: str
     status: "DeviceStatus"
+    created_on: str
+    updated_on: Optional[str] = None
+    deleted_on: Optional[str] = None
     _trust: bool = field(alias="_trust", default=False)
 
 
@@ -51,6 +56,9 @@ class DeviceUpdatedEvent(Event):
     product_team_id: UUID
     ods_code: str
     status: "DeviceStatus"
+    created_on: str
+    updated_on: str
+    deleted_on: Optional[str] = None
 
 
 @dataclass(kw_only=True, slots=True)
@@ -149,18 +157,28 @@ class Device(AggregateRoot):
     status: DeviceStatus = Field(default=DeviceStatus.ACTIVE)
     product_team_id: UUID
     ods_code: str
+    created_on: datetime = Field(default_factory=datetime.utcnow, immutable=True)
+    updated_on: Optional[datetime] = Field(default=None)
+    deleted_on: Optional[datetime] = Field(default=None)
     keys: dict[str, DeviceKey] = Field(default_factory=dict, exclude=True)
     questionnaire_responses: dict[str, list[QuestionnaireResponse]] = Field(
         default_factory=lambda: defaultdict(list), exclude=True
     )
 
     def update(self, **kwargs) -> DeviceUpdatedEvent:
+        if "updated_on" not in kwargs:
+            kwargs["updated_on"] = datetime.utcnow()
         device_data = self._update(data=kwargs)
         event = DeviceUpdatedEvent(**device_data)
         return self.add_event(event)
 
     def delete(self) -> DeviceUpdatedEvent:
-        return self.update(status=DeviceStatus.INACTIVE)
+        deletion_datetime = datetime.utcnow()
+        return self.update(
+            status=DeviceStatus.INACTIVE,
+            updated_on=deletion_datetime,
+            deleted_on=deletion_datetime,
+        )
 
     def add_key(self, type: str, key: str, _trust=False) -> DeviceKeyAddedEvent:
         if key in self.keys:
diff --git a/src/layers/domain/core/tests/test_device.py b/src/layers/domain/core/tests/test_device.py
index 07d129e41..9fa7b49ac 100644
--- a/src/layers/domain/core/tests/test_device.py
+++ b/src/layers/domain/core/tests/test_device.py
@@ -1,3 +1,4 @@
+from datetime import datetime
 from itertools import chain
 
 import pytest
@@ -58,15 +59,32 @@ def another_questionnaire_response() -> QuestionnaireResponse:
     return questionnaire.respond(responses=[{"question1": ["bye"]}])
 
 
+def test_device_created_with_datetime(device: Device):
+    assert isinstance(device.created_on, datetime)
+    assert device.updated_on == None
+    assert device.deleted_on == None
+
+
 def test_device_update(device: Device):
+    device_created_on = device.created_on
+    device_updated_on = device.updated_on
     event = device.update(name="bar")
     assert device.name == "bar"
+    assert device.deleted_on == None
+    assert isinstance(device.updated_on, datetime)
+    assert device.updated_on != device_updated_on
+    assert device.created_on == device_created_on
     assert isinstance(event, DeviceUpdatedEvent)
 
 
 def test_device_delete(device: Device):
+    device_created_on = device.created_on
+    assert device.deleted_on == None
     event = device.delete()
     assert device.status == DeviceStatus.INACTIVE
+    assert device.created_on == device_created_on
+    assert isinstance(device.deleted_on, datetime)
+    assert device.updated_on == device.deleted_on
     assert isinstance(event, DeviceUpdatedEvent)
 
 
diff --git a/src/layers/domain/repository/marshall.py b/src/layers/domain/repository/marshall.py
index 11ccf42bf..a058732fe 100644
--- a/src/layers/domain/repository/marshall.py
+++ b/src/layers/domain/repository/marshall.py
@@ -3,7 +3,7 @@
 from .errors import UnableToUnmarshall
 
 MARSHALL_FUNCTION_BY_TYPE = {
-    type(None): (lambda _: {"Null": True}),
+    type(None): (lambda _: {"NULL": True}),
     bool: (lambda x: {"BOOL": x}),
     int: (lambda x: {"N": str(x)}),
     float: (lambda x: {"N": str(x)}),
@@ -28,7 +28,7 @@ def _unmarshall_mapping(mapping: dict[str, dict[str, Any]]) -> dict[str, Any]:
 def unmarshall_value(record: dict[str, str | dict | list]):
     ((_type_name, value),) = record.items()
     match _type_name:
-        case "Null":
+        case "NULL":
             return None
         case "S":
             return str(value)
diff --git a/src/layers/domain/repository/tests/test_marshall.py b/src/layers/domain/repository/tests/test_marshall.py
index 13f40ee99..c8c099056 100644
--- a/src/layers/domain/repository/tests/test_marshall.py
+++ b/src/layers/domain/repository/tests/test_marshall.py
@@ -12,7 +12,7 @@ def __init__(self, depth=0):
 @pytest.mark.parametrize(
     "value,expected",
     [
-        [None, {"Null": True}],
+        [None, {"NULL": True}],
         ["foo", {"S": "foo"}],
         [123, {"N": "123"}],
         [True, {"BOOL": True}],
@@ -29,7 +29,7 @@ def __init__(self, depth=0):
             ],
             {
                 "L": [
-                    {"Null": True},
+                    {"NULL": True},
                     {"N": "1"},
                     {"N": "2.0"},
                     {"S": "3"},
@@ -51,7 +51,7 @@ def __init__(self, depth=0):
             },
             {
                 "M": {
-                    "none": {"Null": True},
+                    "none": {"NULL": True},
                     "bool": {"BOOL": False},
                     "int": {"N": "1"},
                     "float": {"N": "2"},
@@ -71,7 +71,7 @@ def test_marshall_value(value, expected):
 @pytest.mark.parametrize(
     "value,expected",
     [
-        [{"Null": True}, None],
+        [{"NULL": True}, None],
         [{"BOOL": False}, False],
         [{"BOOL": True}, True],
         [{"N": "0"}, 0.0],
@@ -79,7 +79,7 @@ def test_marshall_value(value, expected):
         [{"N": "1.2"}, 1.2],
         [{"S": "x"}, "x"],
         [{"L": []}, []],
-        [{"L": [{"Null": True}]}, [None]],
+        [{"L": [{"NULL": True}]}, [None]],
         [{"M": {}}, {}],
         [{"M": {"foo": {"BOOL": False}, "bar": {"N": "1"}}}, {"foo": False, "bar": 1}],
     ],
diff --git a/src/layers/etl_utils/io/__init__.py b/src/layers/etl_utils/io/__init__.py
index 8aa2db2aa..756107f7b 100644
--- a/src/layers/etl_utils/io/__init__.py
+++ b/src/layers/etl_utils/io/__init__.py
@@ -1,6 +1,7 @@
 import json
 import pickle
 from collections import deque
+from datetime import datetime
 from io import BytesIO
 from typing import IO
 from uuid import UUID
@@ -18,6 +19,8 @@ def default(self, obj):
             return list(obj)
         if isinstance(obj, UUID):
             return str(obj)
+        if isinstance(obj, datetime):
+            return str(obj)
         return json.JSONEncoder.default(self, obj)
 
 
diff --git a/src/layers/sds/cpm_translation/tests/test_cpm_translation.py b/src/layers/sds/cpm_translation/tests/test_cpm_translation.py
index 516694332..9a8178aa7 100644
--- a/src/layers/sds/cpm_translation/tests/test_cpm_translation.py
+++ b/src/layers/sds/cpm_translation/tests/test_cpm_translation.py
@@ -1,3 +1,4 @@
+from datetime import datetime
 from itertools import chain
 from string import ascii_letters, digits
 from typing import Generator
@@ -212,7 +213,14 @@ def test_delete_devices(repository: DeviceRepository):
         product_team_id=_device_1.product_team_id,
         ods_code=_device_1.ods_code,
         status=DeviceStatus.INACTIVE,
+        created_on=_device_1.created_on,
+        updated_on=event_1.updated_on,
+        deleted_on=event_1.deleted_on,
     )
+    assert isinstance(event_1.updated_on, datetime)
+    assert isinstance(event_1.deleted_on, datetime)
+    assert event_1.deleted_on == event_1.updated_on
+
     assert event_2 == DeviceUpdatedEvent(
         id=_device_2.id,
         name=_device_2.name,
@@ -220,7 +228,13 @@ def test_delete_devices(repository: DeviceRepository):
         product_team_id=_device_2.product_team_id,
         ods_code=_device_2.ods_code,
         status=DeviceStatus.INACTIVE,
+        created_on=_device_2.created_on,
+        updated_on=event_2.updated_on,
+        deleted_on=event_2.deleted_on,
     )
+    assert isinstance(event_2.updated_on, datetime)
+    assert isinstance(event_2.deleted_on, datetime)
+    assert event_2.deleted_on == event_2.updated_on
 
 
 @pytest.mark.integration