diff --git a/api_deploy/schema.py b/api_deploy/schema.py
index 1f73623..9f980b2 100644
--- a/api_deploy/schema.py
+++ b/api_deploy/schema.py
@@ -1,9 +1,23 @@
 from typing import Dict
 import yaml
+import re
 
 yaml.Dumper.ignore_aliases = lambda *args: True
 
 
+# pyyaml interprents strings which are octals as int so we're overriding this behaviour
+def represent_str(self, data):
+    """Custom string representer that forces quoting for strings with leading zeros"""
+    # Only quote strings that look like numbers with leading zeros (but not just "0")
+    if re.match(r'^0[0-9]+$', data):
+        return self.represent_scalar('tag:yaml.org,2002:str', data, style='"')
+    # Use default behavior for all other strings
+    return yaml.Dumper.represent_str(self, data)
+
+
+# Attach custom representer to tye default YAML dumper
+yaml.add_representer(str, represent_str)
+
 class YamlDict(Dict):
     def __init__(self, schema) -> None:
         content = yaml.load(schema, yaml.Loader) or {}
@@ -34,4 +48,5 @@ def dump(self, sort_keys=False):
             'x-amazon-apigateway-request-validators': self.get('x-amazon-apigateway-request-validators', {}),
             'x-amazon-apigateway-minimum-compression-size': 0                                   ,
         }
+
         return yaml.dump(data, sort_keys=sort_keys)
diff --git a/tests/openapi/complex_source.yml b/tests/openapi/complex_source.yml
index e8edff7..6eb831d 100644
--- a/tests/openapi/complex_source.yml
+++ b/tests/openapi/complex_source.yml
@@ -403,6 +403,13 @@ components:
           enum:
             - draft
             - submitted
+        offerCode:
+          type: string
+          readOnly: true
+          enum:
+            - "0116"
+            - "0118"
+            - "0119"
         stateTransitions:
           $ref: "#/components/schemas/StateTransitionList"
         _meta:
diff --git a/tests/openapi/complex_target.yml b/tests/openapi/complex_target.yml
index 439c1f5..d70e421 100644
--- a/tests/openapi/complex_target.yml
+++ b/tests/openapi/complex_target.yml
@@ -1252,6 +1252,7 @@ components:
                 - attachments
                 - comment
                 - state
+                - offerCode
                 - stateTransitions
                 - _meta
                 - _links
@@ -1307,6 +1308,13 @@ components:
                     enum:
                     - draft
                     - submitted
+                  offerCode:
+                    type: string
+                    readOnly: true
+                    enum:
+                      - "0116"
+                      - "0118"
+                      - "0119"
                   stateTransitions:
                     type: array
                     readOnly: true
@@ -1704,6 +1712,7 @@ components:
       - attachments
       - comment
       - state
+      - offerCode
       - stateTransitions
       - _meta
       - _links
@@ -1759,6 +1768,13 @@ components:
           enum:
           - draft
           - submitted
+        offerCode:
+          type: string
+          readOnly: true
+          enum:
+            - "0116"
+            - "0118"
+            - "0119"
         stateTransitions:
           type: array
           readOnly: true