If it has been more than 24 hours since this user has last sync'd AND the session counter (See IDVAULT_COUNT1) is greater than 4, then we sync right away.
This mechanism is in place so that user's who don't run their Notes clients for extended periods will still regularly perform ID file Syncs.
It does take into account weekends, holidays, and company shutdowns so that we do not have a sync storm after those events.