diff --git a/src/core/gcal-timeline.c b/src/core/gcal-timeline.c
index 2369651e..bacc2fa6 100644
--- a/src/core/gcal-timeline.c
+++ b/src/core/gcal-timeline.c
@@ -77,6 +77,7 @@ struct _GcalTimeline
 
   GCancellable       *cancellable;
 
+  GHashTable         *queued_adds;
   GQueue             *event_queue;
   GSource            *timeline_source;
 
@@ -101,6 +102,13 @@ static GParamSpec *properties [N_PROPS] = { NULL, };
  * Auxiliary methods
  */
 
+static gchar*
+format_subscriber_event_id (GcalTimelineSubscriber *subscriber,
+                            GcalEvent              *event)
+{
+  return g_strdup_printf ("%s:%s", G_OBJECT_TYPE_NAME (subscriber), gcal_event_get_uid (event));
+}
+
 static void
 queue_data_free (QueueData *queue_data)
 {
@@ -118,6 +126,7 @@ queue_event_data (GcalTimeline           *self,
                   GcalEvent              *old_event,
                   gboolean                update_range_tree)
 {
+  g_autofree gchar *subscriber_event_id = NULL;
   QueueData *queue_data;
 
   queue_data = g_new0 (QueueData, 1);
@@ -128,7 +137,49 @@ queue_event_data (GcalTimeline           *self,
   queue_data->old_event = old_event ? g_object_ref (old_event) : NULL;
   queue_data->update_range_tree = update_range_tree;
 
+  subscriber_event_id = format_subscriber_event_id (subscriber, event);
+
+  switch (queue_event)
+    {
+    case ADD_EVENT:
+    case UPDATE_EVENT:
+      break;
+    case REMOVE_EVENT:
+        {
+          GList *queued_add_link;
+
+          queued_add_link = g_hash_table_lookup (self->queued_adds, subscriber_event_id);
+          if (queued_add_link)
+            {
+              QueueData *queued_add = queued_add_link->data;
+
+              GCAL_TRACE_MSG ("Removing ADD_EVENT for event '%s' (%s) from event queue",
+                              gcal_event_get_summary (event),
+                              subscriber_event_id);
+
+              g_hash_table_remove (self->queued_adds, subscriber_event_id);
+              g_queue_delete_link (self->event_queue, queued_add_link);
+              queue_data_free (queued_add);
+              return;
+            }
+        }
+      break;
+    }
+
   g_queue_push_tail (self->event_queue, queue_data);
+
+  switch (queue_event)
+    {
+    case ADD_EVENT:
+      g_hash_table_insert (self->queued_adds,
+                           g_steal_pointer (&subscriber_event_id),
+                           g_queue_peek_tail_link (self->event_queue));
+      break;
+
+    case UPDATE_EVENT:
+    case REMOVE_EVENT:
+      break;
+    }
 }
 
 static inline gboolean
@@ -608,6 +659,7 @@ timeline_source_dispatch (GSource     *source,
   while (processed_events < BATCH_SIZE && !g_queue_is_empty (self->event_queue))
     {
       GcalTimelineSubscriber *subscriber;
+      g_autofree gchar *subscriber_event_id = NULL;
       GcalRange *event_range;
       QueueData *queue_data;
       GcalEvent *event;
@@ -617,10 +669,12 @@ timeline_source_dispatch (GSource     *source,
       event = queue_data->event;
       subscriber = queue_data->subscriber;
       event_range = gcal_event_get_range (event);
+      subscriber_event_id = format_subscriber_event_id (subscriber, event);
 
       /* The subscriber may have been removed already */
       if (!g_hash_table_contains (self->subscribers, subscriber))
         {
+          g_hash_table_remove (self->queued_adds, subscriber_event_id);
           queue_data_free (queue_data);
           continue;
         }
@@ -628,10 +682,12 @@ timeline_source_dispatch (GSource     *source,
       switch (queue_data->queue_event)
         {
         case ADD_EVENT:
-          GCAL_TRACE_MSG ("Processing ADD_EVENT for event '%s' (%s)",
+          GCAL_TRACE_MSG ("Processing ADD_EVENT for event '%s' (%s) (in queued_adds: %d)",
                           gcal_event_get_summary (event),
-                          gcal_event_get_uid (event));
+                          gcal_event_get_uid (event),
+                          g_hash_table_contains (self->queued_adds, subscriber_event_id));
 
+          g_hash_table_remove (self->queued_adds, subscriber_event_id);
           if (queue_data->update_range_tree)
             gcal_range_tree_add_range (self->events, event_range, g_object_ref (event));
 
@@ -708,6 +764,7 @@ gcal_timeline_finalize (GObject *object)
   g_clear_pointer (&self->events, gcal_range_tree_unref);
   g_clear_pointer (&self->calendars, g_hash_table_destroy);
   g_clear_pointer (&self->subscribers, g_hash_table_destroy);
+  g_clear_pointer (&self->queued_adds, g_hash_table_destroy);
   g_clear_pointer (&self->subscriber_ranges, gcal_range_tree_unref);
 
   g_source_destroy (self->timeline_source);
@@ -829,6 +886,7 @@ gcal_timeline_init (GcalTimeline *self)
   self->subscribers = g_hash_table_new_full (NULL, NULL, g_object_unref, (GDestroyNotify) gcal_range_unref);
   self->subscriber_ranges = gcal_range_tree_new ();
   self->event_queue = g_queue_new ();
+  self->queued_adds = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
 
   /* Timeline source */
   timeline_source = (TimelineSource*) g_source_new (&timeline_source_funcs, sizeof (TimelineSource));