diff --git a/celery/app/base.py b/celery/app/base.py
index cf2a3ac3671..842e3416070 100644
--- a/celery/app/base.py
+++ b/celery/app/base.py
@@ -733,7 +733,8 @@ def send_task(self, name, args=None, kwargs=None, countdown=None,
             options, route_name or name, args, kwargs, task_type)
         if expires is not None:
             if isinstance(expires, datetime):
-                expires_s = (maybe_make_aware(expires) - self.now()).total_seconds()
+                expires_s = (maybe_make_aware(
+                    expires) - self.now()).total_seconds()
             else:
                 expires_s = expires
 
diff --git a/requirements/test-ci-default.txt b/requirements/test-ci-default.txt
index 953ed9aecc7..e6a3014cf7f 100644
--- a/requirements/test-ci-default.txt
+++ b/requirements/test-ci-default.txt
@@ -18,6 +18,7 @@
 -r extras/cosmosdbsql.txt
 -r extras/cassandra.txt
 -r extras/azureblockblob.txt
+git+https://github.com/celery/kombu.git
 
 # SQS dependencies other than boto
 pycurl==7.43.0.5  # Latest version with wheel built (for appveyor)
diff --git a/t/unit/tasks/test_tasks.py b/t/unit/tasks/test_tasks.py
index 89689914f26..ebfe89e1ad7 100644
--- a/t/unit/tasks/test_tasks.py
+++ b/t/unit/tasks/test_tasks.py
@@ -983,6 +983,17 @@ def test_regular_task(self):
                 name='George Costanza', test_eta=True, test_expires=True,
             )
 
+            # With ETA, absolute expires in the past in ISO format.
+            presult2 = self.mytask.apply_async(
+                kwargs={'name': 'George Costanza'},
+                eta=self.now() + timedelta(days=1),
+                expires=self.now() - timedelta(days=2),
+            )
+            self.assert_next_task_data_equal(
+                consumer, presult2, self.mytask.name,
+                name='George Costanza', test_eta=True, test_expires=True,
+            )
+
             # Default argsrepr/kwargsrepr behavior
             presult2 = self.mytask.apply_async(
                 args=('spam',), kwargs={'name': 'Jerry Seinfeld'}