diff --git a/truss/remote/baseten/api.py b/truss/remote/baseten/api.py
index 4f548dcd5..e071a43a7 100644
--- a/truss/remote/baseten/api.py
+++ b/truss/remote/baseten/api.py
@@ -1,5 +1,4 @@
 import logging
-from typing import Optional
 
 import requests
 from truss.remote.baseten.auth import AuthService
@@ -59,38 +58,57 @@ def model_s3_upload_credentials(self):
 
     def create_model_from_truss(
         self,
-        model_name,
-        s3_key,
-        config,
-        semver_bump,
-        client_version,
-        is_trusted=False,
-        model_id: Optional[str] = None,
+        model_name: str,
+        s3_key: str,
+        config: str,
+        semver_bump: str,
+        client_version: str,
+        is_trusted: bool,
     ):
-        if model_id:
-            mutation = "create_model_version_from_truss"
-            first_arg = f'model_id: "{model_id}"'
-        else:
-            mutation = "create_model_from_truss"
-            first_arg = f'name: "{model_name}"'
-
         query_string = f"""
         mutation {{
-        {mutation}({first_arg},
-                    s3_key: "{s3_key}",
-                    config: "{config}",
-                    semver_bump: "{semver_bump}",
-                    client_version: "{client_version}",
-                    is_trusted: {'true' if is_trusted else 'false'}
-    ) {{
-            id,
-            name,
-            version_id
+            create_model_from_truss(
+                name: "{model_name}",
+                s3_key: "{s3_key}",
+                config: "{config}",
+                semver_bump: "{semver_bump}",
+                client_version: "{client_version}",
+                is_trusted: {'true' if is_trusted else 'false'}
+            ) {{
+                id,
+                name,
+                version_id
+            }}
         }}
+        """
+        resp = self._post_graphql_query(query_string)
+        return resp["data"]["create_model_from_truss"]
+
+    def create_model_version_from_truss(
+        self,
+        model_id: str,
+        s3_key: str,
+        config: str,
+        semver_bump: str,
+        client_version: str,
+        is_trusted: bool,
+    ):
+        query_string = f"""
+        mutation {{
+            create_model_version_from_truss(
+                model_id: "{model_id}"
+                s3_key: "{s3_key}",
+                config: "{config}",
+                semver_bump: "{semver_bump}",
+                client_version: "{client_version}",
+                is_trusted: {'true' if is_trusted else 'false'}
+            ) {{
+                id
+            }}
         }}
         """
         resp = self._post_graphql_query(query_string)
-        return resp["data"][mutation]
+        return resp["data"]["create_model_version_from_truss"]
 
     def create_development_model_from_truss(
         self,
diff --git a/truss/remote/baseten/core.py b/truss/remote/baseten/core.py
index d92557ad1..7707bbce2 100644
--- a/truss/remote/baseten/core.py
+++ b/truss/remote/baseten/core.py
@@ -106,8 +106,8 @@ def create_truss_service(
     model_name: str,
     s3_key: str,
     config: str,
-    semver_bump: Optional[str] = "MINOR",
-    is_trusted: Optional[bool] = False,
+    semver_bump: str = "MINOR",
+    is_trusted: bool = False,
     is_draft: Optional[bool] = False,
     model_id: Optional[str] = None,
 ) -> Tuple[str, str]:
@@ -133,15 +133,28 @@ def create_truss_service(
             f"truss=={truss.version()}",
             is_trusted,
         )
-    else:
+
+        return (model_version_json["id"], model_version_json["version_id"])
+
+    if model_id is None:
         model_version_json = api.create_model_from_truss(
-            model_name,
-            s3_key,
-            config,
-            semver_bump,
-            f"truss=={truss.version()}",
-            is_trusted,
-            model_id,
+            model_name=model_name,
+            s3_key=s3_key,
+            config=config,
+            semver_bump=semver_bump,
+            client_version=f"truss=={truss.version()}",
+            is_trusted=is_trusted,
         )
-
-    return (model_version_json["id"], model_version_json["version_id"])
+        return (model_version_json["id"], model_version_json["version_id"])
+
+    # Case where there is a model id already, create another version
+    model_version_json = api.create_model_version_from_truss(
+        model_id=model_id,
+        s3_key=s3_key,
+        config=config,
+        semver_bump=semver_bump,
+        client_version=f"truss=={truss.version()}",
+        is_trusted=is_trusted,
+    )
+    model_version_id = model_version_json["id"]
+    return (model_id, model_version_id)