diff --git a/server/tests-py/queries/explain/simple_query_mssql.yaml b/server/tests-py/queries/explain/simple_query_mssql.yaml
index 529598bca93..8d5c926c1f2 100644
--- a/server/tests-py/queries/explain/simple_query_mssql.yaml
+++ b/server/tests-py/queries/explain/simple_query_mssql.yaml
@@ -3,18 +3,14 @@ url: /v1/graphql/explain
 status: 200
 response:
   - field: user
-    sql: |-
-      SELECT ISNULL((SELECT [t_user1].[id] AS [id],
-             [t_user1].[name] AS [name],
-             [t_user1].[age] AS [age]
-      FROM [dbo].[user] AS [t_user1]
-      OUTER APPLY (SELECT *
-                   FROM OPENJSON((N''+NCHAR(123)+''+NCHAR(34)+'positionalArguments'+NCHAR(34)+''+NCHAR(58)+''+NCHAR(91)+''+NCHAR(93)+','+NCHAR(34)+'namedArguments'+NCHAR(34)+''+NCHAR(58)+''+NCHAR(123)+''+NCHAR(125)+','+NCHAR(34)+'session'+NCHAR(34)+''+NCHAR(58)+''+NCHAR(123)+''+NCHAR(125)+''+NCHAR(125)+''))
-                        WITH ([session] NVARCHAR(MAX) AS JSON,
-                             [namedArguments] NVARCHAR(MAX) AS JSON,
-                             [positionalArguments] NVARCHAR(MAX) AS JSON) AS [row]) 
-      AS [row]
-      FOR JSON PATH), '[]')
+    sql:
+      "SELECT ISNULL((SELECT [t_user1].[id] AS [id],\n       [t_user1].[name] AS\
+      \ [name],\n       [t_user1].[age] AS [age]\nFROM [dbo].[user] AS [t_user1]\nOUTER\
+      \ APPLY (SELECT *\n             FROM OPENJSON((N''+NCHAR(123)+''+NCHAR(34)+'positionalArguments'+NCHAR(34)+''+NCHAR(58)+''+NCHAR(91)+''+NCHAR(93)+','+NCHAR(34)+'namedArguments'+NCHAR(34)+''+NCHAR(58)+''+NCHAR(123)+''+NCHAR(125)+','+NCHAR(34)+'session'+NCHAR(34)+''+NCHAR(58)+''+NCHAR(123)+''+NCHAR(125)+''+NCHAR(125)+''))\n\
+      \                  WITH ([session] NVARCHAR(MAX) AS JSON,\n                  \
+      \     [namedArguments] NVARCHAR(MAX) AS JSON,\n                       [positionalArguments]\
+      \ NVARCHAR(MAX) AS JSON) AS [row]\n             WHERE (1=1)) \nAS [row]\nWHERE\
+      \ ((1=1))\nFOR JSON PATH), '[]')"
 query:
   query:
     query: |
diff --git a/server/tests-py/test_graphql_queries.py b/server/tests-py/test_graphql_queries.py
index 534e53637a4..d79f90b2973 100644
--- a/server/tests-py/test_graphql_queries.py
+++ b/server/tests-py/test_graphql_queries.py
@@ -388,10 +388,7 @@ class TestGraphQLQueryOffsets:
     def dir(cls):
         return 'queries/graphql_query/offset'
 
-# FIXME: MSSQL subscriptions multiplexing regression
-# https://github.com/hasura/graphql-engine-mono/issues/1434
-# @pytest.mark.parametrize("transport", ['http', 'websocket', 'subscription'])
-@pytest.mark.parametrize("transport", ['http', 'websocket'])
+@pytest.mark.parametrize("transport", ['http', 'websocket', 'subscription'])
 @pytest.mark.parametrize("backend", ['mssql', 'postgres'])
 @usefixtures('per_class_tests_db_state')
 class TestGraphQLQueryBoolExpBasicCommon:
@@ -588,10 +585,7 @@ class TestGraphQLInheritedRoles:
         check_query_f(hge_ctx, self.dir() + '/inherited_role_with_some_roles_having_no_permissions.yaml')
 
 
-# FIXME: MSSQL subscriptions multiplexing regression
-# https://github.com/hasura/graphql-engine-mono/issues/1434
-# @pytest.mark.parametrize("transport", ['http', 'websocket', 'subscription'])
-@pytest.mark.parametrize("transport", ['http', 'websocket'])
+@pytest.mark.parametrize("transport", ['http', 'websocket', 'subscription'])
 @pytest.mark.parametrize("backend", ['postgres', 'mssql'])
 @usefixtures('per_class_tests_db_state')
 class TestGraphQLQueryBoolExpSearchCommon:
@@ -949,10 +943,7 @@ class TestUnauthorizedRolePermission:
     def test_unauth_role(self, hge_ctx, transport):
         check_query_f(hge_ctx, self.dir() + '/unauthorized_role.yaml', transport, False)
 
-# FIXME: MSSQL subscriptions multiplexing regression
-# https://github.com/hasura/graphql-engine-mono/issues/1434
-# @pytest.mark.parametrize("backend", ['postgres', 'mssql'])
-@pytest.mark.parametrize("backend", ['postgres'])
+@pytest.mark.parametrize("backend", ['postgres', 'mssql'])
 @usefixtures('per_class_tests_db_state')
 class TestGraphQLExplain:
     @classmethod
diff --git a/server/tests-py/test_subscriptions.py b/server/tests-py/test_subscriptions.py
index 18a85fb33fd..93b5fa32425 100644
--- a/server/tests-py/test_subscriptions.py
+++ b/server/tests-py/test_subscriptions.py
@@ -251,10 +251,7 @@ class TestSubscriptionLiveQueries:
         with pytest.raises(queue.Empty):
             ev = ws_client.get_ws_event(3)
 
-# FIXME: MSSQL subscriptions multiplexing regression
-# https://github.com/hasura/graphql-engine-mono/issues/1434
-# @pytest.mark.parametrize("backend", ['mssql', 'postgres'])
-@pytest.mark.parametrize("backend", ['postgres'])
+@pytest.mark.parametrize("backend", ['mssql', 'postgres'])
 @usefixtures('per_class_tests_db_state')
 class TestSubscriptionMultiplexing:
 
@@ -298,9 +295,6 @@ class TestSubscriptionMultiplexing:
         return response
 
 
-# FIXME: MSSQL subscriptions multiplexing regression
-# https://github.com/hasura/graphql-engine-mono/issues/1434
-# @pytest.mark.parametrize("backend", ['mssql', 'postgres'])
 @pytest.mark.parametrize("backend", ['postgres'])
 @usefixtures('per_class_tests_db_state', 'ws_conn_init')
 class TestSubscriptionUDFWithSessionArg: