diff --git a/python/lightning_sdk/api/job_api.py b/python/lightning_sdk/api/job_api.py
index 527f489d..cfdf0928 100644
--- a/python/lightning_sdk/api/job_api.py
+++ b/python/lightning_sdk/api/job_api.py
@@ -496,6 +496,8 @@ def stream_logs(
                         return  # idle timeout on a snapshot: treat the stream as finished
                     except WebSocketConnectionClosedException:
                         break  # fall through to reconnect logic
+                    if isinstance(message, bytes):
+                        message = message.decode("utf-8", errors="replace")
                     if message == "":
                         break
                     yield from _decode_log_messages(message, timestamps=timestamps)
diff --git a/python/lightning_sdk/api/logs_api.py b/python/lightning_sdk/api/logs_api.py
index cde0602b..fa6b9904 100644
--- a/python/lightning_sdk/api/logs_api.py
+++ b/python/lightning_sdk/api/logs_api.py
@@ -541,6 +541,8 @@ def follow(
                         continue
                     except (WebSocketConnectionClosedException, OSError):
                         break  # fall through to the reconnect decision
+                    if isinstance(message, bytes):
+                        message = message.decode("utf-8", errors="replace")
                     if message == "":
                         break
                     entries = parse_log_entries(message)
diff --git a/python/lightning_sdk/studio.py b/python/lightning_sdk/studio.py
index 2e44741b..55b890c1 100644
--- a/python/lightning_sdk/studio.py
+++ b/python/lightning_sdk/studio.py
@@ -12,7 +12,7 @@
 from lightning_sdk.api.utils import AccessibleResource, raise_access_error_if_not_allowed
 from lightning_sdk.base_studio import BaseStudio
 from lightning_sdk.constants import _LIGHTNING_DEBUG
-from lightning_sdk.exceptions import NotSupportedError, OutOfCapacityError
+from lightning_sdk.exceptions import OutOfCapacityError
 from lightning_sdk.lightning_cloud.openapi import V1ClusterType, V1Endpoint
 from lightning_sdk.machine import DEFAULT_MACHINE, CloudProvider, Machine
 from lightning_sdk.organization import Organization
@@ -357,7 +357,11 @@ def start(
 
         Raises:
             RuntimeError: If the Studio is already running on a different machine or is not stopped.
-            RuntimeError: If the requested machine is not supported or has no available capacity.
+            RuntimeError: If the requested machine has no available capacity.
+
+        Warns:
+            UserWarning: If the requested machine is not a known machine type for the selected
+                cloud account. It is treated as a custom instance type and passed through as-is.
         """
         # Check to see if we're inside a studio and if its running
         current_studio_machine = None
@@ -410,9 +414,10 @@ def start(
         if not self._studio_api.machine_is_supported(
             new_machine, self._teamspace.id, self.cloud_account, _get_org_id(self._teamspace)
         ):
-            raise NotSupportedError(
-                "Requested machine is not supported in the selected cloud account. "
-                "Try a different machine or cloud account by setting the `machine` or `cloud_account` argument."
+            warnings.warn(
+                f"Machine {new_machine} is a custom instance type that hasn't been vetted by Lightning. "
+                "It may not be available in the selected cloud account and startup may fail. "
+                "Continue at your own risk."
             )
 
         if not self._studio_api.machine_has_capacity(
diff --git a/python/tests/core/studio/test_studio_start.py b/python/tests/core/studio/test_studio_start.py
index 7abbfbf7..5f4f480f 100644
--- a/python/tests/core/studio/test_studio_start.py
+++ b/python/tests/core/studio/test_studio_start.py
@@ -1,6 +1,8 @@
 import os
 from unittest import mock
 
+import pytest
+
 from lightning_sdk.lightning_cloud.openapi import (
     CloudSpaceServiceCreateCloudSpaceBody,
     CloudSpaceServiceStartCloudSpaceInstanceBody,
@@ -41,6 +43,7 @@ def _list_cloudspaces_side_effect(*args, **kwargs):
     return _list_cloudspaces_side_effect
 
 
+@pytest.mark.parametrize("machine_supported", [True, False])
 @mock.patch(
     "lightning_sdk.lightning_cloud.openapi.api.cluster_service_api.ClusterServiceApi.cluster_service_list_default_cluster_accelerators",
     autospec=True,
@@ -99,6 +102,7 @@ def test_studio_start(
     mock_list_project_clusters,
     mock_list_clusters,
     mock_list_accelerators,
+    machine_supported,
 ):
     # Setup state from internal_studio_start_mocker
     status = {"st-abc": None}
@@ -207,7 +211,7 @@ def _create_lightning_run_side_effect(body, project_id, cloudspace_id, **kwargs)
     mock_list_cloudspaces.side_effect = list_cloudspaces_side_effect(existing_studios)
     mock_create_cloudspace.side_effect = _create_cloudspace_side_effect
     mock_create_lightning_run.side_effect = _create_lightning_run_side_effect
-    mock_machine_is_supported.return_value = True
+    mock_machine_is_supported.return_value = machine_supported
 
     # Setup teamspace and org mocks
     mock_get_teamspace.return_value = V1Project(
@@ -225,7 +229,12 @@ def _create_lightning_run_side_effect(body, project_id, cloudspace_id, **kwargs)
     assert studio.machine is None
     assert studio.teamspace.start_studios_on_interruptible is True
 
-    studio.start()
+    if machine_supported:
+        studio.start()
+    else:
+        # unvetted machines emit a warning but still start
+        with pytest.warns(UserWarning, match="custom instance type"):
+            studio.start()
 
     assert studio.status == Status.Running
     assert studio.interruptible is True