Overdue settings configured globally - all invoices use same interval, limits, and send time Daily Send Time applies to ALL overdue emails - cannot send different times based on overdue age Minute selector only allows 15-minute increments (0, 15, 30, 45) External server processes missions every minute - actual send may be ±1 minute from configured time Overdue emails don't send for paid invoices - mission automatically cancelled when invoice marked paid Stop conditions checked after each send - if email count reaches limit on same day as day limit, stops immediately No way to send overdue emails for invoices with deleted customers Interval calculation is fixed; cannot vary interval based on overdue age (same 3-day interval throughout) No built-in email bounce handling or unsubscribe