We just got hit with a few critical customer transaction e-mails failing to be delivery to Postmark due to a human error at Postmark, port 2525 was blocked. (as seen in the Postmark status page). We were looking everywhere, Gravity Forms, WP Engine and Postmark losing confidence until we spotted the recent 3 day late status update.
Is there any way to provide optional logging to troubleshoot SMTP connection issues?
https://wordpress.org/plugins/postmark-approved-wordpress-plugin/