diff --git a/notifications_routing/router.py b/notifications_routing/router.py
index beae0fb9c9e5cf0fa6e3f9cdeb868919d34eb54b..d70bf9befefeed547d76bac4085486957e3a7f21 100644
--- a/notifications_routing/router.py
+++ b/notifications_routing/router.py
@@ -114,11 +114,11 @@ class Router(megabus.Listener):
         groups = self.data_source.get_channel_groups(channel_id)
         logging.debug("channel %s groups %s", users, groups)
 
-        if groups:
-            unsubscribed_users = self.data_source.get_channel_unsubscribed_users(channel_id)
-            logging.debug("channel %s unsubscribed users %s", channel_id, unsubscribed_users)
-            audit_notification(notification_id, {"event": "Unsubscribed users", "targets": unsubscribed_users})
+        unsubscribed_users = self.data_source.get_channel_unsubscribed_users(channel_id)
+        logging.debug("channel %s unsubscribed users %s", channel_id, unsubscribed_users)
+        audit_notification(notification_id, {"event": "Unsubscribed users", "targets": unsubscribed_users})
 
+        if groups:
             self.add_users_from_groups(notification_id, channel_id, users, groups, unsubscribed_users)
 
         logging.debug("channel %s final users %s", channel_id, users)
@@ -150,8 +150,13 @@ class Router(megabus.Listener):
 
         return subscribed_target_users
 
-    def process_users(self, message):
-        """Process unique users list, if targeted, intersection or standard post."""
+    def process_users(self, message) -> List[Dict[str, str]]:
+        """Process unique users list, if targeted, intersection or standard post.
+
+        :param message: Dict with keys from OutputMessageKeys
+        :return: A list of user data in the format of dicts containing user_id, username, email and last_login
+        :raises: NotFoundDataSourceError, MultipleResultsFoundError
+        """
         if OutputMessageKeys.PRIVATE in message and message[OutputMessageKeys.PRIVATE]:
             audit_notification(message[OutputMessageKeys.ID], {"event": "Start processing targeted notification"})
             logging.debug("Processing direct notification %s", message[OutputMessageKeys.ID])
@@ -159,17 +164,27 @@ class Router(megabus.Listener):
                 message[OutputMessageKeys.ID],
                 message[OutputMessageKeys.CHANNEL_ID],
             )
+
             if not target_users:
                 logging.debug("no target_users found for notification %s", message[OutputMessageKeys.ID])
-                return
+                return []
             if OutputMessageKeys.INTERSECTION in message and message[OutputMessageKeys.INTERSECTION]:
                 logging.debug("Processing intersection target users for %s", message[OutputMessageKeys.ID])
                 channel_users = self.get_channel_users(
                     message[OutputMessageKeys.ID], message[OutputMessageKeys.CHANNEL_ID]
                 )
+
+                audit_notification(
+                    message[OutputMessageKeys.ID],
+                    {"event": "Target users", "total": len(target_users), "users": target_users},
+                )
+                audit_notification(
+                    message[OutputMessageKeys.ID],
+                    {"event": "Channel users for intersection", "total": len(channel_users), "users": channel_users},
+                )
                 if not channel_users:
                     logging.debug("no channel_users to intersect for channel %s", message[OutputMessageKeys.CHANNEL_ID])
-                    return
+                    return []
                 target_users = [x for x in target_users if x in channel_users]
 
             return target_users
@@ -179,20 +194,21 @@ class Router(megabus.Listener):
             target_users = self.get_channel_users(message[OutputMessageKeys.ID], message[OutputMessageKeys.CHANNEL_ID])
             if not target_users:
                 logging.debug("no channel_users for channel %s", message[OutputMessageKeys.CHANNEL_ID])
-                return
+                return []
 
             return target_users
 
     def process_message(self, message):
         """Process a message according to user and default preferences and sends to available delivery channels."""
         target_users = self.process_users(message)
-        if not target_users:
-            return
-
         audit_notification(
             message[OutputMessageKeys.ID],
             {"event": "Expanded recipients", "total": len(target_users), "targets": target_users},
         )
+
+        if not target_users:
+            return
+
         for user in target_users:
             # Never logged in users, apply default preferences
             has_logged_in = self.data_source.LAST_LOGIN in user and user.get(self.data_source.LAST_LOGIN)