The way the Replyco system is set up -- When a customer emails us, then sends us a new email and another email, the system sees it as a new email and the email thread would go to the last page (If sorted to see the Oldest messages first). It's a critical case where the old email is skipped.
For email support accounts that receive 100+ emails a day, it's important that we get informed if there's an email with multiple follow up and still not responded to.
Or a way that we can easily see if a thread has multiple emails that need a response, as soon as possible.