When someone emails a ticket desk, the sender's 'ticket received' email uses the FROM email that is set in the email template, rather then the override email address set.
Even with this set, it ignores it for the person opening the ticket via email. However, the staff assigned to the desk gets an email with the correct overridden email address set.
So the bugs is that for people sending emails to open tickets, they receive confirmation with the incorrect FROM address.
Blesta v4.3.1
PHP 7.0