diff --git a/swh/lister/bitbucket/tasks.py b/swh/lister/bitbucket/tasks.py
--- a/swh/lister/bitbucket/tasks.py
+++ b/swh/lister/bitbucket/tasks.py
@@ -2,6 +2,7 @@
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
+import logging
 import random
 from celery import group
 
@@ -11,6 +12,8 @@
 
 GROUP_SPLIT = 10000
 
+logger = logging.getLogger(__name__)
+
 
 def new_lister(api_baseurl='https://api.bitbucket.org/2.0', per_page=100):
     return BitBucketLister(api_baseurl=api_baseurl, per_page=per_page)
@@ -39,11 +42,11 @@
     random.shuffle(ranges)
     promise = group(range_bitbucket_lister.s(minv, maxv, **lister_args)
                     for minv, maxv in ranges)()
-    self.log.debug('%s OK (spawned %s subtasks)' % (self.name, len(ranges)))
+    logger.debug('%s OK (spawned %s subtasks)', (self.name, len(ranges)))
     try:
         promise.save()  # so that we can restore the GroupResult in tests
     except (NotImplementedError, AttributeError):
-        self.log.info('Unable to call save_group with current result backend.')
+        logger.info('Unable to call save_group with current result backend.')
     return promise.id
 
 
diff --git a/swh/lister/core/indexing_lister.py b/swh/lister/core/indexing_lister.py
--- a/swh/lister/core/indexing_lister.py
+++ b/swh/lister/core/indexing_lister.py
@@ -148,8 +148,6 @@
         t = self.db_session.query(func.min(self.MODEL.indexable)).first()
         if t:
             return t[0]
-        else:
-            return None
 
     def db_last_index(self):
         """Look in the db for the largest indexable value
@@ -160,8 +158,6 @@
         t = self.db_session.query(func.max(self.MODEL.indexable)).first()
         if t:
             return t[0]
-        else:
-            return None
 
     def disable_deleted_repo_tasks(self, start, end, keep_these):
         """Disable tasks for repos that no longer exist between start and end.
@@ -222,11 +218,12 @@
                                 index)
                     return
                 index = next_index
+                logger.debug('Index: %s', index)
                 yield i
 
         for i in ingest_indexes():
             if (i % 20) == 0:
-                logger.info('flushing updates')
+                logger.info('flushing updates at index %s', i)
                 self.db_session.commit()
                 self.db_session = self.mk_session()