diff --git a/schemas/api/trains/TrainDetails.json b/schemas/api/trains/TrainDetails.json
index 306ee22..8ef3c80 100644
--- a/schemas/api/trains/TrainDetails.json
+++ b/schemas/api/trains/TrainDetails.json
@@ -2,11 +2,6 @@
     "$schema": "https://json-schema.org/draft-07/schema#",
     "title": "TrainByHeadcodeResponse",
     "$defs": {
-        "DateTimeTZ": {
-            "type": "string",
-            "format": "date-time",
-            "description": "An ISO-8601 timestamp"
-        },
         "ServiceLocation": {
             "type": "object",
             "description": "A specific location along the services journey",
@@ -67,47 +62,58 @@
                     "description": "The formation ID at this location"
                 },
                 "pta": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Public time of arrival"
                 },
                 "wta": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Working time of arrival"
                 },
                 "wtp": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Working time of pass"
                 },
                 "ptd": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Public time of departure"
                 },
                 "wtd": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Working time of departure"
                 },
                 "eta": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Estimated time of arrival"
                 },
                 "etd": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Estimated time of departure"
                 },
                 "etp": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Estimated time of pass"
                 },
                 "ata": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Actual time of arrival"
                 },
                 "atd": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Actual time of departure"
                 },
                 "atp": {
-                    "$ref": "#/$defs/DateTimeTZ",
+                    "type": "string",
+                    "format": "date-time",
                     "title": "Actual time of pass"
                 }
             },