diff --git a/codegen/sdk-codegen/aws-models/route-53.json b/codegen/sdk-codegen/aws-models/route-53.json
index cb6b2468d68..13b6fcde63a 100644
--- a/codegen/sdk-codegen/aws-models/route-53.json
+++ b/codegen/sdk-codegen/aws-models/route-53.json
@@ -279,7 +279,7 @@
                     "parameters": {
                         "Region": {
                             "builtIn": "AWS::Region",
-                            "required": false,
+                            "required": true,
                             "documentation": "The AWS region used to dispatch the request.",
                             "type": "String"
                         },
@@ -1731,8 +1731,8 @@
                             },
                             "params": {
                                 "UseDualStack": false,
-                                "UseFIPS": false,
-                                "Region": "aws-cn-global"
+                                "Region": "aws-cn-global",
+                                "UseFIPS": false
                             }
                         },
                         {
@@ -1753,8 +1753,8 @@
                             },
                             "params": {
                                 "UseDualStack": false,
-                                "UseFIPS": false,
-                                "Region": "aws-global"
+                                "Region": "aws-global",
+                                "UseFIPS": false
                             }
                         },
                         {
@@ -1775,8 +1775,8 @@
                             },
                             "params": {
                                 "UseDualStack": false,
-                                "UseFIPS": false,
-                                "Region": "aws-iso-global"
+                                "Region": "aws-iso-global",
+                                "UseFIPS": false
                             }
                         },
                         {
@@ -1797,8 +1797,8 @@
                             },
                             "params": {
                                 "UseDualStack": false,
-                                "UseFIPS": false,
-                                "Region": "aws-iso-b-global"
+                                "Region": "aws-iso-b-global",
+                                "UseFIPS": false
                             }
                         },
                         {
@@ -1819,8 +1819,8 @@
                             },
                             "params": {
                                 "UseDualStack": false,
-                                "UseFIPS": false,
-                                "Region": "aws-us-gov-global"
+                                "Region": "aws-us-gov-global",
+                                "UseFIPS": false
                             }
                         },
                         {
@@ -1832,8 +1832,8 @@
                             },
                             "params": {
                                 "UseDualStack": false,
-                                "UseFIPS": false,
                                 "Region": "us-east-1",
+                                "UseFIPS": false,
                                 "Endpoint": "https://example.com"
                             }
                         },
@@ -1844,8 +1844,8 @@
                             },
                             "params": {
                                 "UseDualStack": false,
-                                "UseFIPS": true,
                                 "Region": "us-east-1",
+                                "UseFIPS": true,
                                 "Endpoint": "https://example.com"
                             }
                         },
@@ -1856,8 +1856,8 @@
                             },
                             "params": {
                                 "UseDualStack": true,
-                                "UseFIPS": false,
                                 "Region": "us-east-1",
+                                "UseFIPS": false,
                                 "Endpoint": "https://example.com"
                             }
                         }
@@ -2933,6 +2933,12 @@
                         "smithy.api#enumValue": "ap-south-1"
                     }
                 },
+                "ap_south_2": {
+                    "target": "smithy.api#Unit",
+                    "traits": {
+                        "smithy.api#enumValue": "ap-south-2"
+                    }
+                },
                 "ap_southeast_1": {
                     "target": "smithy.api#Unit",
                     "traits": {
@@ -10055,6 +10061,12 @@
                         "smithy.api#enumValue": "ap-south-1"
                     }
                 },
+                "ap_south_2": {
+                    "target": "smithy.api#Unit",
+                    "traits": {
+                        "smithy.api#enumValue": "ap-south-2"
+                    }
+                },
                 "af_south_1": {
                     "target": "smithy.api#Unit",
                     "traits": {
@@ -11602,6 +11614,12 @@
                         "smithy.api#enumValue": "ap-south-1"
                     }
                 },
+                "ap_south_2": {
+                    "target": "smithy.api#Unit",
+                    "traits": {
+                        "smithy.api#enumValue": "ap-south-2"
+                    }
+                },
                 "ap_northeast_1": {
                     "target": "smithy.api#Unit",
                     "traits": {