diff --git a/airbyte-ci/connectors/metadata_service/lib/metadata_service/gcs_upload.py b/airbyte-ci/connectors/metadata_service/lib/metadata_service/gcs_upload.py
index 268332bcb89a..695e90a46d81 100644
--- a/airbyte-ci/connectors/metadata_service/lib/metadata_service/gcs_upload.py
+++ b/airbyte-ci/connectors/metadata_service/lib/metadata_service/gcs_upload.py
@@ -217,7 +217,11 @@ def upload_metadata_to_gcs(bucket_name: str, metadata_file_path: Path, validator
     if metadata is None:
         raise ValueError(f"Metadata file {metadata_file_path} is invalid for uploading: {error}")
 
-    service_account_info = json.loads(os.environ.get("GCS_CREDENTIALS"))
+    gcs_creds = os.environ.get("GCS_CREDENTIALS")
+    if not gcs_creds:
+        raise ValueError("Please set the GCS_CREDENTIALS env var.")
+
+    service_account_info = json.loads(gcs_creds)
     credentials = service_account.Credentials.from_service_account_info(service_account_info)
     storage_client = storage.Client(credentials=credentials)
     bucket = storage_client.bucket(bucket_name)
diff --git a/airbyte-ci/connectors/metadata_service/lib/metadata_service/validators/metadata_validator.py b/airbyte-ci/connectors/metadata_service/lib/metadata_service/validators/metadata_validator.py
index a4006d4837d5..94bc6942c5b6 100644
--- a/airbyte-ci/connectors/metadata_service/lib/metadata_service/validators/metadata_validator.py
+++ b/airbyte-ci/connectors/metadata_service/lib/metadata_service/validators/metadata_validator.py
@@ -71,7 +71,7 @@ def validate_metadata_images_in_dockerhub(
 
     print(f"Checking that the following images are on dockerhub: {images_to_check}")
     for image, version in images_to_check:
-        if not is_image_on_docker_hub(image, version):
+        if not is_image_on_docker_hub(image, version, retries=3):
             return False, f"Image {image}:{version} does not exist in DockerHub"
 
     return True, None
@@ -151,7 +151,7 @@ def validate_metadata_base_images_in_dockerhub(
 ) -> ValidationResult:
     metadata_definition_dict = metadata_definition.dict()
 
-    image_address = get(metadata_definition_dict, "data.connectorOptions.baseImage")
+    image_address = get(metadata_definition_dict, "data.connectorBuildOptions.baseImage")
     if image_address is None:
         return True, None
 
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/__init__.py b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/__init__.py
index cd7cbc8f7685..685f9639ac5a 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/__init__.py
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/__init__.py
@@ -7,28 +7,45 @@
 
 def list_all_paths_in_fixture_directory(folder_name: str) -> List[str]:
     file_path = os.path.join(os.path.dirname(__file__), folder_name)
+
+    # If folder_name has subdirectories, os.walk will return a list of tuples,
+    # one for folder_name and one for each of its subdirectories.
+    fixture_files = []
     for root, dirs, files in os.walk(file_path):
-        return [os.path.join(root, file_name) for file_name in files]
+        fixture_files.extend(os.path.join(root, file_name) for file_name in files)
+    return fixture_files
 
 
 @pytest.fixture(scope="session")
 def valid_metadata_yaml_files() -> List[str]:
-    return list_all_paths_in_fixture_directory("metadata_validate/valid")
+    files = list_all_paths_in_fixture_directory("metadata_validate/valid")
+    if not files:
+        pytest.fail("No files found in metadata_validate/valid")
+    return files
 
 
 @pytest.fixture(scope="session")
 def invalid_metadata_yaml_files() -> List[str]:
-    return list_all_paths_in_fixture_directory("metadata_validate/invalid")
+    files = list_all_paths_in_fixture_directory("metadata_validate/invalid")
+    if not files:
+        pytest.fail("No files found in metadata_validate/invalid")
+    return files
 
 
 @pytest.fixture(scope="session")
 def valid_metadata_upload_files() -> List[str]:
-    return list_all_paths_in_fixture_directory("metadata_upload/valid")
+    files = list_all_paths_in_fixture_directory("metadata_upload/valid")
+    if not files:
+        pytest.fail("No files found in metadata_upload/valid")
+    return files
 
 
 @pytest.fixture(scope="session")
 def invalid_metadata_upload_files() -> List[str]:
-    return list_all_paths_in_fixture_directory("metadata_upload/invalid")
+    files = list_all_paths_in_fixture_directory("metadata_upload/invalid")
+    if not files:
+        pytest.fail("No files found in metadata_upload/invalid")
+    return files
 
 
 @pytest.fixture(scope="session")
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_breaking_change_image_tag_does_not_exist.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_breaking_change_image_tag_does_not_exist.yaml
index 0b4174048ec0..685f75ed08e1 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_breaking_change_image_tag_does_not_exist.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_breaking_change_image_tag_does_not_exist.yaml
@@ -16,7 +16,7 @@ data:
   releaseStage: alpha
   releases:
     breakingChanges:
-      6.0.0: # tag does not exist
+      0.0.0: # tag does not exist
         upgradeDeadline: 2023-08-22
         message: "This version made a change."
   documentationUrl: https://docs.airbyte.com/integrations/sources/onesignal
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_cloud_image_tag_does_not_exist.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_cloud_image_tag_does_not_exist.yaml
index 461e53e021d5..799a7d4f3424 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_cloud_image_tag_does_not_exist.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_cloud_image_tag_does_not_exist.yaml
@@ -18,7 +18,7 @@ data:
     cloud:
       enabled: true
       dockerRepository: airbyte/exists-3
-      dockerImageTag: 6.6.6 # tag does not exist
+      dockerImageTag: 99.99.99 # tag does not exist
     oss:
       enabled: true
       dockerRepository: airbyte/exists-4
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_main_image_tag_does_not_exist.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_main_image_tag_does_not_exist.yaml
index 1ea6ea03f992..5e5732263165 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_main_image_tag_does_not_exist.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_main_image_tag_does_not_exist.yaml
@@ -5,7 +5,7 @@ data:
   connectorType: source
   dockerRepository: airbyte/exists-1
   githubIssueLabel: source-alloydb-strict-encrypt
-  dockerImageTag: 6.6.6 # tag does not exist
+  dockerImageTag: 99.99.99 # tag does not exist
   documentationUrl: https://docs.airbyte.com/integrations/sources/existingsource
   connectorSubtype: database
   releaseStage: generally_available
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_normalization_image_tag_does_not_exist.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_normalization_image_tag_does_not_exist.yaml
index 2eb1dedd082d..7f4375c486f2 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_normalization_image_tag_does_not_exist.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_normalization_image_tag_does_not_exist.yaml
@@ -13,7 +13,7 @@ data:
   normalizationConfig:
     normalizationIntegrationType: postgres
     normalizationRepository: airbyte/exists-2
-    dockerImageTag: 6.6.6 # tag does not exist
+    normalizationTag: 99.99.99 # tag does not exist
   registries:
     cloud:
       enabled: true
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_oss_repo_does_not_exist.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_oss_repo_does_not_exist.yaml
index b1712fef132d..ffb3735e5655 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_oss_repo_does_not_exist.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/tag_nonexistent/metadata_oss_repo_does_not_exist.yaml
@@ -22,6 +22,6 @@ data:
     oss:
       enabled: true
       dockerRepository: airbyte/exists-4
-      dockerImageTag: 6.6.6 # tag does not exist
+      dockerImageTag: 99.99.99 # tag does not exist
   tags:
     - language:java
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_base_image_nonexistent/metadata_main_image_tag_does_not_exist_but_is_overrode.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_image_nonexistent/metadata_main_image_tag_does_not_exist_but_is_overrode.yaml
similarity index 94%
rename from airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_base_image_nonexistent/metadata_main_image_tag_does_not_exist_but_is_overrode.yaml
rename to airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_image_nonexistent/metadata_main_image_tag_does_not_exist_but_is_overrode.yaml
index 59c8d124b3f8..81ee107bd267 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_base_image_nonexistent/metadata_main_image_tag_does_not_exist_but_is_overrode.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_image_nonexistent/metadata_main_image_tag_does_not_exist_but_is_overrode.yaml
@@ -5,7 +5,7 @@ data:
   connectorType: source
   dockerRepository: airbyte/exists-1
   githubIssueLabel: source-alloydb-strict-encrypt
-  dockerImageTag: 6.6.6 # tag does not exist
+  dockerImageTag: 99.99.99 # tag does not exist
   documentationUrl: https://docs.airbyte.com/integrations/sources/existingsource
   connectorSubtype: database
   releaseStage: generally_available
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_base_image_nonexistent/metadata_main_repo_does_not_exist_but_is_overrode.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_image_nonexistent/metadata_main_repo_does_not_exist_but_is_overrode.yaml
similarity index 100%
rename from airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_base_image_nonexistent/metadata_main_repo_does_not_exist_but_is_overrode.yaml
rename to airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/valid_overrides_but_image_nonexistent/metadata_main_repo_does_not_exist_but_is_overrode.yaml
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/valid/metadata_base_image_exists.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/valid/metadata_base_image_exists.yaml
index b107fd4c8d49..9fae02a082aa 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/valid/metadata_base_image_exists.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/valid/metadata_base_image_exists.yaml
@@ -6,7 +6,7 @@ data:
     hosts:
       - zopim.com
   connectorBuildOptions:
-    baseImage: docker.io/airbyte/python-connector-base:1.1.0@sha256:bd98f6505c6764b1b5f99d3aedc23dfc9e9af631a62533f60eb32b1d3dbab20c
+    baseImage: docker.io/airbyte/base-repo-exists:1.1.0@sha256:bd98f6505c6764b1b5f99d3aedc23dfc9e9af631a62533f60eb32b1d3dbab20c
   connectorSubtype: api
   connectorType: source
   definitionId: 40d24d0f-b8f9-4fe0-9e6c-b06c0f3f45e4
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/base_image_nonexistent/metadata_base_image_digest_does_not_exists.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/base_image_nonexistent/metadata_base_image_digest_does_not_exists.yaml
similarity index 88%
rename from airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/base_image_nonexistent/metadata_base_image_digest_does_not_exists.yaml
rename to airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/base_image_nonexistent/metadata_base_image_digest_does_not_exists.yaml
index 335960385af7..0f20fe4d28c8 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/base_image_nonexistent/metadata_base_image_digest_does_not_exists.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/base_image_nonexistent/metadata_base_image_digest_does_not_exists.yaml
@@ -6,7 +6,7 @@ data:
     hosts:
       - zopim.com
   connectorBuildOptions:
-    baseImage: docker.io/airbyte/python-connector-base:1.1.0@sha256:doesnotexists
+    baseImage: docker.io/airbyte/base-repo-exists:1.1.0@sha256:MISSINGSHA
   connectorSubtype: api
   connectorType: source
   definitionId: 40d24d0f-b8f9-4fe0-9e6c-b06c0f3f45e4
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/base_image_nonexistent/metadata_base_image_name_does_not_exists.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/base_image_nonexistent/metadata_base_image_name_does_not_exists.yaml
similarity index 100%
rename from airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/base_image_nonexistent/metadata_base_image_name_does_not_exists.yaml
rename to airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/base_image_nonexistent/metadata_base_image_name_does_not_exists.yaml
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/base_image_nonexistent/metadata_base_image_tag_does_not_exists.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/base_image_nonexistent/metadata_base_image_tag_does_not_exists.yaml
similarity index 82%
rename from airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/base_image_nonexistent/metadata_base_image_tag_does_not_exists.yaml
rename to airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/base_image_nonexistent/metadata_base_image_tag_does_not_exists.yaml
index b377a89fff7c..fed77cbd1399 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_upload/invalid/base_image_nonexistent/metadata_base_image_tag_does_not_exists.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/base_image_nonexistent/metadata_base_image_tag_does_not_exists.yaml
@@ -6,7 +6,7 @@ data:
     hosts:
       - zopim.com
   connectorBuildOptions:
-    baseImage: docker.io/airbyte/python-connector-base:does-not-exists@sha256:bd98f6505c6764b1b5f99d3aedc23dfc9e9af631a62533f60eb32b1d3dbab20c
+    baseImage: docker.io/airbyte/base-repo-exists:99.99.99@sha256:bd98f6505c6764b1b5f99d3aedc23dfc9e9af631a62533f60eb32b1d3dbab20c
   connectorSubtype: api
   connectorType: source
   definitionId: 40d24d0f-b8f9-4fe0-9e6c-b06c0f3f45e4
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_breaking_change_versions_under_releases.yml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_breaking_change_versions_under_releases.yml
new file mode 100644
index 000000000000..27e2c17d1abf
--- /dev/null
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_breaking_change_versions_under_releases.yml
@@ -0,0 +1,18 @@
+metadataSpecVersion: 1.0
+data:
+  name: AlloyDB for PostgreSQL
+  definitionId: 1fa90628-2b9e-11ed-a261-0242ac120002
+  connectorType: source
+  dockerRepository: airbyte/image-exists-1
+  githubIssueLabel: source-alloydb-strict-encrypt
+  dockerImageTag: 0.0.1
+  documentationUrl: https://docs.airbyte.com/integrations/sources/alloydb
+  connectorSubtype: database
+  releaseStage: generally_available
+  license: MIT
+  releasestests/fixtures/metadata_validate/invalid/metadata_breaking_change_versions_under_releases.yml:
+    2.1.3:
+      message: "This version changes the connector’s authentication method from `ApiKey` to `oAuth`, per the [API guide](https://amazon-sqs.com/api/someguide)."
+      upgradeDeadline: 2023-08-22
+  tags:
+    - language:java
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_breaking_changes_not_under_releases.yml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_breaking_changes_not_under_releases.yml
new file mode 100644
index 000000000000..e2b9918cccf0
--- /dev/null
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_breaking_changes_not_under_releases.yml
@@ -0,0 +1,18 @@
+metadataSpecVersion: 1.0
+data:
+  name: AlloyDB for PostgreSQL
+  definitionId: 1fa90628-2b9e-11ed-a261-0242ac120002
+  connectorType: source
+  dockerRepository: airbyte/image-exists-1
+  githubIssueLabel: source-alloydb-strict-encrypt
+  dockerImageTag: 0.0.1
+  documentationUrl: https://docs.airbyte.com/integrations/sources/alloydb
+  connectorSubtype: database
+  releaseStage: generally_available
+  license: MIT
+  breakingChanges:
+    2.1.3:
+      message: "This version changes the connector’s authentication method from `ApiKey` to `oAuth`, per the [API guide](https://amazon-sqs.com/api/someguide)."
+      upgradeDeadline: 2023-08-22
+  tags:
+    - language:java
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_invalid_base_image_no_sha.yml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_invalid_base_image_no_sha.yml
new file mode 100644
index 000000000000..91de8734a4bf
--- /dev/null
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_invalid_base_image_no_sha.yml
@@ -0,0 +1,29 @@
+data:
+  allowedHosts:
+    hosts:
+      - "*.googleapis.com"
+  connectorBuildOptions:
+    baseImage: docker.io/airbyte/base-repo-exists:1.1.0
+  connectorSubtype: file
+  connectorType: source
+  definitionId: 71607ba1-c0ac-4799-8049-7f4b90dd50f7
+  dockerImageTag: 0.3.7
+  dockerRepository: airbyte/source-google-sheets
+  githubIssueLabel: source-google-sheets
+  icon: google-sheets.svg
+  license: Elv2
+  name: Google Sheets
+  registries:
+    cloud:
+      enabled: true
+    oss:
+      enabled: true
+  releaseStage: generally_available
+  documentationUrl: https://docs.airbyte.com/integrations/sources/google-sheets
+  tags:
+    - language:python
+  ab_internal:
+    sl: 300
+    ql: 400
+  supportLevel: certified
+metadataSpecVersion: "1.0"
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_major_version_no_breaking_change_entry_for_version.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_major_version_no_breaking_change_entry_for_version.yaml
index 46f419ed2838..86bdde803417 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_major_version_no_breaking_change_entry_for_version.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/invalid/metadata_major_version_no_breaking_change_entry_for_version.yaml
@@ -16,9 +16,10 @@ data:
       enabled: true
   releaseStage: alpha
   releases:
-    1.0.0:
-      upgradeDeadline: 2023-08-22
-      message: "This version made a change."
+    breakingChanges:
+      1.0.0:
+        upgradeDeadline: 2023-08-22
+        message: "This version made a change."
   documentationUrl: https://docs.airbyte.com/integrations/sources/onesignal
   tags:
     - language:python
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/valid/metadata_build_base_image.yaml b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/valid/metadata_build_base_image.yaml
index df8b955c2c26..4b2c65d6ebea 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/valid/metadata_build_base_image.yaml
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/fixtures/metadata_validate/valid/metadata_build_base_image.yaml
@@ -3,7 +3,7 @@ data:
     hosts:
       - "*.googleapis.com"
   connectorBuildOptions:
-    baseImage: airbyte/python-connector-base:1.0.0
+    baseImage: docker.io/airbyte/base-repo-exists:1.1.0@sha256:bd98f6505c6764b1b5f99d3aedc23dfc9e9af631a62533f60eb32b1d3dbab20c
   connectorSubtype: file
   connectorType: source
   definitionId: 71607ba1-c0ac-4799-8049-7f4b90dd50f7
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/test_commands.py b/airbyte-ci/connectors/metadata_service/lib/tests/test_commands.py
index e8d1858df708..2ef3ec4188fa 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/test_commands.py
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/test_commands.py
@@ -10,12 +10,16 @@
 from metadata_service.gcs_upload import MetadataUploadInfo, UploadedFile
 from metadata_service.validators.metadata_validator import ValidatorOptions
 from pydantic import BaseModel, ValidationError, error_wrappers
+from test_gcs_upload import stub_is_image_on_docker_hub
 
 
 # TEST VALIDATE COMMAND
-def test_valid_metadata_yaml_files(valid_metadata_yaml_files, tmp_path):
+def test_valid_metadata_yaml_files(mocker, valid_metadata_yaml_files, tmp_path):
     runner = CliRunner()
 
+    # Mock dockerhub for base image checks
+    mocker.patch("metadata_service.validators.metadata_validator.is_image_on_docker_hub", side_effect=stub_is_image_on_docker_hub)
+
     assert len(valid_metadata_yaml_files) > 0, "No files found"
 
     for file_path in valid_metadata_yaml_files:
@@ -30,13 +34,13 @@ def test_invalid_metadata_yaml_files(invalid_metadata_yaml_files, tmp_path):
 
     for file_path in invalid_metadata_yaml_files:
         result = runner.invoke(commands.validate, [file_path, str(tmp_path)])
-        assert result.exit_code != 0, f"Validation succeeded (when it shouldve failed) for {file_path}"
+        assert result.exit_code != 0, f"Validation succeeded (when it should have failed) for {file_path}"
 
 
 def test_metadata_file_not_found_fails(tmp_path):
     runner = CliRunner()
     result = runner.invoke(commands.validate, ["non_existent_file.yaml", str(tmp_path)])
-    assert result.exit_code != 0, "Validation succeeded (when it shouldve failed) for non_existent_file.yaml"
+    assert result.exit_code != 0, "Validation succeeded (when it should have failed) for non_existent_file.yaml"
 
 
 def test_docs_path_not_found_fails(valid_metadata_yaml_files):
@@ -45,7 +49,7 @@ def test_docs_path_not_found_fails(valid_metadata_yaml_files):
     assert len(valid_metadata_yaml_files) > 0, "No files found"
 
     result = runner.invoke(commands.validate, [valid_metadata_yaml_files[0], "non_existent_docs_path"])
-    assert result.exit_code != 0, "Validation succeeded (when it shouldve failed) for non_existent_docs_path"
+    assert result.exit_code != 0, "Validation succeeded (when it should have failed) for non_existent_docs_path"
 
 
 def mock_metadata_upload_info(
diff --git a/airbyte-ci/connectors/metadata_service/lib/tests/test_gcs_upload.py b/airbyte-ci/connectors/metadata_service/lib/tests/test_gcs_upload.py
index 819ca93c6d18..26c6260adf8e 100644
--- a/airbyte-ci/connectors/metadata_service/lib/tests/test_gcs_upload.py
+++ b/airbyte-ci/connectors/metadata_service/lib/tests/test_gcs_upload.py
@@ -4,6 +4,7 @@
 
 import json
 from pathlib import Path
+from typing import Optional
 
 import pytest
 import yaml
@@ -14,15 +15,19 @@
 from metadata_service.validators.metadata_validator import ValidatorOptions
 from pydash.objects import get
 
-# Version exists by default, but "666" is bad! (6.0.0 too since breaking changes regex tho)
-MOCK_VERSIONS_THAT_DO_NOT_EXIST = ["6.6.6", "6.0.0"]
+MOCK_VERSIONS_THAT_DO_NOT_EXIST = ["99.99.99", "0.0.0"]
+MISSING_SHA = "MISSINGSHA"
 DOCS_PATH = "/docs"
 MOCK_DOC_URL_PATH = "integrations/sources/existingsource.md"
 VALID_DOC_FILE_PATH = Path(DOCS_PATH) / MOCK_DOC_URL_PATH
 
 
-def stub_is_image_on_docker_hub(image_name: str, version: str) -> bool:
-    return "exists" in image_name and version not in MOCK_VERSIONS_THAT_DO_NOT_EXIST
+def stub_is_image_on_docker_hub(image_name: str, version: str, digest: Optional[str] = None, retries: int = 0, wait_sec: int = 30) -> bool:
+    image_repo_exists = "exists" in image_name
+    version_exists = version not in MOCK_VERSIONS_THAT_DO_NOT_EXIST
+    sha_is_valid = (digest != MISSING_SHA) if digest is not None else True
+    image_exists = all([image_repo_exists, version_exists, sha_is_valid])
+    return image_exists
 
 
 @pytest.fixture(autouse=True)
@@ -38,6 +43,30 @@ def fake_exists(self):
     monkeypatch.setattr(Path, "exists", fake_exists)
 
 
+def assert_upload_invalid_metadata_fails_correctly(metadata_file_path: Path, expected_error_match: str, validate_success_error_match: str):
+    """
+    When attempting to upload invalid metadata, we expect it to fail in a predictable way, depending on what is exactly invalid
+    about the file. This helper aims to make it easier for a developer who is adding new test cases to figure out that their test
+    is failing because the test data that should be invalid is passing all of the validation steps.
+
+    Because we don't exit the uploading process if validation fails, this case often looks like a weird error message that is hard to
+    grok.
+    """
+    try:
+        with pytest.raises(ValueError, match=expected_error_match) as exc_info:
+            gcs_upload.upload_metadata_to_gcs(
+                "my_bucket",
+                metadata_file_path,
+                validator_opts=ValidatorOptions(docs_path=DOCS_PATH),
+            )
+        print(f"Upload raised {exc_info.value}")
+    except AssertionError as e:
+        if validate_success_error_match in str(e):
+            raise AssertionError(f"Validation succeeded (when it should have failed) for {metadata_file_path}") from e
+        else:
+            raise e
+
+
 def setup_upload_mocks(
     mocker,
     version_blob_md5_hash,
@@ -215,6 +244,7 @@ def test_upload_metadata_to_gcs_valid_metadata(
     mocker.spy(gcs_upload, "_doc_upload")
 
     for valid_metadata_upload_file in valid_metadata_upload_files:
+        print(f"\nTesting upload of valid metadata file: " + valid_metadata_upload_file)
         metadata_file_path = Path(valid_metadata_upload_file)
         metadata = ConnectorMetadataDefinitionV0.parse_obj(yaml.safe_load(metadata_file_path.read_text()))
 
@@ -323,31 +353,44 @@ def test_upload_metadata_to_gcs_non_existent_metadata_file():
         )
 
 
-def test_upload_invalid_metadata_to_gcs(invalid_metadata_yaml_files):
+def test_upload_invalid_metadata_to_gcs(mocker, invalid_metadata_yaml_files):
+    # Mock dockerhub
+    mocker.patch("metadata_service.validators.metadata_validator.is_image_on_docker_hub", side_effect=stub_is_image_on_docker_hub)
+
+    # Test that all invalid metadata files throw a ValueError
     for invalid_metadata_file in invalid_metadata_yaml_files:
+        print(f"\nTesting upload of invalid metadata file: " + invalid_metadata_file)
         metadata_file_path = Path(invalid_metadata_file)
-        # If your test fails with 'Please set the DOCKER_HUB_USERNAME and DOCKER_HUB_PASSWORD environment variables.'
-        # then your test data passed validation when it shouldn't have!
-        with pytest.raises(ValueError, match="Validation error"):
-            gcs_upload.upload_metadata_to_gcs(
-                "my_bucket",
-                metadata_file_path,
-                validator_opts=ValidatorOptions(docs_path=DOCS_PATH),
-            )
+
+        error_match_if_validation_fails_as_expected = "Validation error"
+
+        # If validation succeeds, it goes on to upload any new/changed files.
+        # We don't mock the gcs stuff in this test, so it fails trying to
+        # mock compute the md5 hash.
+        error_match_if_validation_succeeds = "Please set the GCS_CREDENTIALS env var."
+
+        assert_upload_invalid_metadata_fails_correctly(
+            metadata_file_path, error_match_if_validation_fails_as_expected, error_match_if_validation_succeeds
+        )
 
 
 def test_upload_metadata_to_gcs_invalid_docker_images(mocker, invalid_metadata_upload_files):
     setup_upload_mocks(mocker, None, None, "new_md5_hash", None, None, None, None, None)
 
-    # Test that all invalid metadata files throw a ValueError
+    # Test that valid metadata files that reference invalid docker images throw a ValueError
     for invalid_metadata_file in invalid_metadata_upload_files:
+        print(f"\nTesting upload of valid metadata file with invalid docker image: " + invalid_metadata_file)
         metadata_file_path = Path(invalid_metadata_file)
-        with pytest.raises(ValueError, match="does not exist in DockerHub"):
-            gcs_upload.upload_metadata_to_gcs(
-                "my_bucket",
-                metadata_file_path,
-                validator_opts=ValidatorOptions(doc_paths=DOCS_PATH),
-            )
+
+        error_match_if_validation_fails_as_expected = "does not exist in DockerHub"
+
+        # If validation succeeds, it goes on to upload any new/changed files.
+        # We mock gcs stuff in this test, so it fails trying to compare the md5 hashes.
+        error_match_if_validation_succeeds = "Unexpected path"
+
+        assert_upload_invalid_metadata_fails_correctly(
+            metadata_file_path, error_match_if_validation_fails_as_expected, error_match_if_validation_succeeds
+        )
 
 
 def test_upload_metadata_to_gcs_with_prerelease(mocker, valid_metadata_upload_files):
@@ -359,6 +402,7 @@ def test_upload_metadata_to_gcs_with_prerelease(mocker, valid_metadata_upload_fi
     doc_upload_spy = mocker.spy(gcs_upload, "_doc_upload")
 
     for valid_metadata_upload_file in valid_metadata_upload_files:
+        print(f"\nTesting prerelease upload of valid metadata file: " + valid_metadata_upload_file)
         # Assuming there is a valid metadata file in the list, if not, you might need to create one
         metadata_file_path = Path(valid_metadata_upload_file)
         prerelease_image_tag = "1.5.6-dev.f80318f754"