I’m investigating modifying the time format of caddy logs to match.
Recognized values are: unix_seconds_float, unix_milli_float, unix_nano, iso8601, rfc3339, rfc3339_nano, wall, wall_milli, wall_nano, common_log. The value may also be custom format per the Go time package layout specification
I may need to post on the opnsense forums to work out how it can be done with the caddy plugin for it.