I've been have intermittent problems with WeatherCal adding/duplicating calendars for locations that I'm already monitoring. After fighting the problem for a couple of weeks I decided to remove syncservices from Espionage's protection. Haven't seen the problem since.
Since the duplicate calendars were sometimes added while I was already logged in and the syncservices folder available I don't think it had anything to do with timing problems at boot time.
Just wondering if you've seen something like this before?