diff --git a/snews/models/messages.py b/snews/models/messages.py
index 8d9b4b2..fd0aed6 100644
--- a/snews/models/messages.py
+++ b/snews/models/messages.py
@@ -9,7 +9,8 @@
 # Third-party modules
 import numpy as np
 from pydantic import (BaseModel, ConfigDict, Field, NonNegativeFloat,
-                      ValidationError, field_validator, model_validator)
+                      NonNegativeInt, ValidationError, field_validator,
+                      model_validator)
 
 # Local modules
 from ..__version__ import schema_version
@@ -232,20 +233,20 @@ class RetractionMessage(DetectorMessageBase):
 
     model_config = ConfigDict(validate_assignment=True)
 
-    retract_message_uid: Optional[str] = Field(
+    retract_message_uuid: Optional[str] = Field(
         default=None,
         title="Unique message ID",
         description="Unique identifier for the message to retract"
     )
 
-    retract_latest: bool = Field(
-        default=False,
+    retract_latest_n: NonNegativeInt = Field(
+        default=0,
         title="Retract Latest Flag",
         description="True if the latest message is being retracted",
     )
 
-    retraction_reason: str = Field(
-        ...,
+    retraction_reason: Optional[str] = Field(
+        default=None,
         title="Retraction reason",
         description="Reason for retraction",
     )
@@ -257,11 +258,11 @@ def _set_tier(cls, values):
 
     @model_validator(mode="after")
     def _validate_model(self):
-        if self.retract_latest and self.retract_message_uid is not None:
-            raise ValueError("retract_message_uuid cannot be specified when retract_latest=True")
+        if self.retract_latest_n > 0 and self.retract_message_uuid is not None:
+            raise ValueError("retract_message_uuid cannot be specified when retract_latest_n > 0")
 
-        if not self.retract_latest and self.retract_message_uid is None:
-            raise ValueError("Must specify either retract_message_uuid or retract_latest=True")
+        if self.retract_latest_n == 0 and self.retract_message_uuid is None:
+            raise ValueError("Must specify either retract_message_uuid or retract_latest_n > 0")
         return self
 
 
diff --git a/snews/schema/RetractionMessage.schema.json b/snews/schema/RetractionMessage.schema.json
index b630146..665b3f3 100644
--- a/snews/schema/RetractionMessage.schema.json
+++ b/snews/schema/RetractionMessage.schema.json
@@ -140,7 +140,7 @@
       "title": "Detector Name",
       "type": "string"
     },
-    "retract_message_uid": {
+    "retract_message_uuid": {
       "anyOf": [
         {
           "type": "string"
@@ -153,22 +153,30 @@
       "description": "Unique identifier for the message to retract",
       "title": "Unique message ID"
     },
-    "retract_latest": {
-      "default": false,
+    "retract_latest_n": {
+      "default": 0,
       "description": "True if the latest message is being retracted",
+      "minimum": 0,
       "title": "Retract Latest Flag",
-      "type": "boolean"
+      "type": "integer"
     },
     "retraction_reason": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "default": null,
       "description": "Reason for retraction",
-      "title": "Retraction reason",
-      "type": "string"
+      "title": "Retraction reason"
     }
   },
   "required": [
     "tier",
-    "detector_name",
-    "retraction_reason"
+    "detector_name"
   ],
   "title": "RetractionMessage",
   "type": "object"
diff --git a/test/models/test_message_models.py b/test/models/test_message_models.py
index d4073fb..6cc711e 100644
--- a/test/models/test_message_models.py
+++ b/test/models/test_message_models.py
@@ -64,7 +64,7 @@
 # Retraction message
 strategy_required_fields_retraction = {
     **strategy_required_fields_base,
-    "retract_message_uid": st.uuids(version=4).map(lambda x: str(x)),
+    "retract_message_uuid": st.uuids(version=4).map(lambda x: str(x)),
     "retraction_reason": st.text(min_size=1),
 }
 
@@ -165,10 +165,10 @@ def test_snews_message_model_retraction_required(**kwargs):
 def test_snews_message_model_retraction_validation_both_indicators(**kwargs):
     with pytest.raises(ValueError) as exc_info:
         msg = RetractionMessage(**kwargs)
-        msg.retract_latest = True
+        msg.retract_latest_n = 3
         msg.retract_message_uid = "1234567890"
 
-    assert "retract_message_uuid cannot be specified when retract_latest=True" in str(
+    assert "retract_message_uuid cannot be specified when retract_latest_n > 0" in str(
         exc_info.value
     )
 
@@ -177,9 +177,9 @@ def test_snews_message_model_retraction_validation_both_indicators(**kwargs):
 def test_snews_message_model_retraction_validation_neither_indicator(**kwargs):
     with pytest.raises(ValueError) as exc_info:
         msg = RetractionMessage(**kwargs)
-        msg.retract_latest = False
-        msg.retract_message_uid = None
+        msg.retract_latest_n = 0
+        msg.retract_message_uuid = None
 
-    assert "Must specify either retract_message_uuid or retract_latest=True" in str(
+    assert "Must specify either retract_message_uuid or retract_latest_n > 0" in str(
         exc_info.value
     )