diff --git a/CHANGES/371.misc b/CHANGES/371.misc
new file mode 100644
index 000000000..4f7236c47
--- /dev/null
+++ b/CHANGES/371.misc
@@ -0,0 +1 @@
+Auto-publish doesn't modify distributions
diff --git a/pulp_python/app/models.py b/pulp_python/app/models.py
index ac2a83b26..1975a4447 100644
--- a/pulp_python/app/models.py
+++ b/pulp_python/app/models.py
@@ -200,13 +200,4 @@ def on_new_version(self, version):
         from pulp_python.app import tasks
 
         if self.autopublish:
-            publication = tasks.publish(
-                repository_version_pk=version.pk,
-            )
-
-            distributions = self.distributions.all()
-
-            if publication and distributions:
-                for distribution in distributions:
-                    distribution.publication = publication
-                    distribution.save()
+            tasks.publish(repository_version_pk=version.pk)
diff --git a/pulp_python/app/serializers.py b/pulp_python/app/serializers.py
index f9b4e6886..505ad3858 100644
--- a/pulp_python/app/serializers.py
+++ b/pulp_python/app/serializers.py
@@ -46,6 +46,28 @@ class PythonDistributionSerializer(core_serializers.DistributionSerializer):
         allow_null=True,
     )
 
+    def validate(self, data):
+        """
+        Ensure publication and repository are not set at the same time.
+
+        This is needed here till https://pulp.plan.io/issues/8761 is resolved.
+        """
+        data = super().validate(data)
+        repository_provided = data.get("repository", None)
+        publication_provided = data.get("publication", None)
+
+        if repository_provided and publication_provided:
+            raise serializers.ValidationError(
+                _(
+                    "Only one of the attributes 'repository' and 'publication' "
+                    "may be used simultaneously."
+                )
+            )
+        if repository_provided or publication_provided:
+            data["repository"] = repository_provided
+            data["publication"] = publication_provided
+        return data
+
     class Meta:
         fields = core_serializers.DistributionSerializer.Meta.fields + ('publication', )
         model = python_models.PythonDistribution
diff --git a/pulp_python/tests/functional/api/test_auto_publish.py b/pulp_python/tests/functional/api/test_auto_publish.py
index 1358125bf..5db677b71 100644
--- a/pulp_python/tests/functional/api/test_auto_publish.py
+++ b/pulp_python/tests/functional/api/test_auto_publish.py
@@ -4,7 +4,7 @@
 
 from pulp_smash import config
 from pulp_smash.pulp3.bindings import monitor_task
-from pulp_smash.pulp3.utils import gen_repo, gen_distribution
+from pulp_smash.pulp3.utils import gen_repo, gen_distribution, download_content_unit
 
 from pulp_python.tests.functional.utils import gen_python_client, gen_python_remote
 from pulp_python.tests.functional.utils import set_up_module as setUpModule  # noqa:F401
@@ -57,13 +57,11 @@ def test_01_sync(self):
         repository_sync_data = RepositorySyncURL(remote=self.remote.pulp_href)
         sync_response = self.repo_api.sync(self.repo.pulp_href, repository_sync_data)
         task = monitor_task(sync_response.task)
-        self.distribution = self.distributions_api.read(self.distribution.pulp_href)
 
         # Check that all the appropriate resources were created
         self.assertGreater(len(task.created_resources), 1)
         self.assertEqual(self.publications_api.list().count, 1)
-        self.assertTrue(self.distribution.publication is not None)
-        self.assertTrue(self.distribution.publication in task.created_resources)
+        download_content_unit(self.cfg, self.distribution.to_dict(), "simple/")
 
         # Sync the repository again. Since there should be no new repository version, there
         # should be no new publications or distributions either.
@@ -78,16 +76,14 @@ def test_02_modify(self):
         self.assertEqual(self.publications_api.list().count, 0)
         self.assertTrue(self.distribution.publication is None)
 
-        # Modify the repository by adding a coment unit
+        # Modify the repository by adding a content unit
         content = self.content_api.list().results[0].pulp_href
         modify_response = self.repo_api.modify(
             self.repo.pulp_href, {"add_content_units": [content]}
         )
         task = monitor_task(modify_response.task)
-        self.distribution = self.distributions_api.read(self.distribution.pulp_href)
 
         # Check that all the appropriate resources were created
         self.assertGreater(len(task.created_resources), 1)
         self.assertEqual(self.publications_api.list().count, 1)
-        self.assertTrue(self.distribution.publication is not None)
-        self.assertTrue(self.distribution.publication in task.created_resources)
+        download_content_unit(self.cfg, self.distribution.to_dict(), "simple/")
diff --git a/requirements.txt b/requirements.txt
index 5199fa95b..278340b2e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-pulpcore>=3.12
+pulpcore>=3.13.0.dev
 pkginfo
 packaging
 bandersnatch==4.4.0