When the Multi-Currency plugin is active: {amount_due} and {invoice_amount} automatically format with currency symbol and decimal places Respects the invoice's currency selection Shows properly formatted currency (e.g., $1,250.00, €1,137.50, £1,100.00) If plugin inactive, shows plain number with $ symbol When Portal Clients plugin is active with client records: If invoice linked to Portal client, customer data pulled from client record Fallback to invoice meta if client not linked Company name and email from first company in Enhancements settings Overdue emails are scheduled via external Portal API server: External server evaluates missions every minute When overdue email is due, server sends webhook trigger to WordPress WordPress Portal plugin receives trigger and composes/sends email