Issue #145 resolved
OS = FreeBSD 12.2-RELEASE-p11 SSHGUARD = 2.4.2_1,1 (binary) FW = PF
BACKEND="/usr/local/libexec/sshg-fw-pf" FILES="/var/log/auth.log /var/log/maillog"
571 logs in /var/log/maillog with: postfix/smtps/smtpd: warning: unknown[a.b.c.d]: SASL LOGIN authentication failed: authentication failure
No logs whatsoever in /var/log/messages showing this to be picked-up by sshguard.
There are many messages regarding blocking IP's for failed login attempts on service SSH.