Explanation of Gradwatch Flushed from Peter:
every day when GW synchs with the sybase data, the data that are not in sybase gets copied to the _flushed tables and then deleted from the main ones. a backup thing.
so the _flushed tables should only increase in size
but i think there are plenty of queries that look for records both in the main and the _flushed tables
so it sort of also keeps track of former applicants