--- main/invoice.js
+++ fix-due-today/invoice.js
@@ -1,4 +1,4 @@
 export function isOverdue(invoice, referenceDate) {
-  // Intentionally wrong: an invoice due today is not overdue.
-  return invoice.status === 'open' && invoice.due_on <= referenceDate;
+  // An invoice due today is not overdue.
+  return invoice.status === 'open' && invoice.due_on < referenceDate;
 }