Index: res/res_calendar.c
===================================================================
--- res/res_calendar.c	(revision 282538)
+++ res/res_calendar.c	(working copy)
@@ -872,6 +872,7 @@
 
 	/* If we don't find the old_event in new_events, then we can safely delete the old_event */
 	if (!(new_event = find_event(new_events, old_event->uid))) {
+		ast_debug(1, "-- %s: %s\n", old_event->uid, old_event->summary);
 		old_event = destroy_event(old_event);
 		return CMP_MATCH;
 	}
@@ -883,6 +884,7 @@
 	/* Since we don't want to mess with cancelling sched events and adding new ones, just
 	 * copy the internals of the new_event to the old_event */
 	copy_event_data(old_event, new_event);
+	ast_debug(1, "== %s: %s\n", new_event->uid, new_event->summary);
 
 	/* Now we can go ahead and unlink the new_event from new_events and unref it so that only completely
 	 * new events remain in the container */
@@ -896,6 +898,7 @@
 {
 	struct ast_calendar_event *new_event = obj;
 	struct ao2_container *events = arg;
+	ast_debug(1, "++ %s: %s\n", new_event->uid, new_event->summary);
 
 	ao2_link(events, new_event);
 	schedule_calendar_event(new_event->owner, new_event, NULL);