Imported subscriptions aren't invoiced twice

When you or your agent bring in a subscription from before your business joined Economico, the daily schedule no longer invoices its past months again. It invoices only what falls due after the subscription is brought in, however long after signup that is, so the invoices you import from your old books are the only ones for those months. Economico’s own invoices for your plan also arrive in your books by themselves; recording one by hand is refused, so it can never block the real one.