Not a major question, but I'm curious.

The MBean Object Name for the JMXConfigurator is "Name=default,Type=ch.qos.logback.classic.jmx.JMXConfigurator". The key names in the key property list appear to be inconsistent with Oracle's JMX best practices document, which recommend using "type" and "name" as the keys, not "Type" and "Name". Per the same document, "Object Names are case sensitive." So these keys do not match the Oracle recommended keys.

Was this inconsistency known or intended?

The only real consequence I can think of for this is that tools that know how to interpret and display the standard "type" and "name" properties may not work properly with Logback's MBean.