lombok.config ignored when using groovy-eclipse-compiler

I'm not entirely sure if this is an issue or something with my settings, but when following the guidance here on getting groovy-eclipse-compiler to work with lombok, my lombok.config file seems to get ignored (I've tried moving it around to no avail).
For example, if I add lombok.log.fieldName = LOG to the lombok.config and update my source code accordingly, everything will work fine in eclipse but running mvn clean compile will lead to the following error:

[ERROR] LOG.debug("test");
[ERROR] ^^^
[ERROR] LOG cannot be resolved

using maven-compiler-plugin without the groovy-eclipse-compiler seems to work fine.
what could be going on here?

Start by reproducing the issue with the project Lombok guidance linked in the report, using groovy-eclipse-compiler and mvn clean compile. Compare the failing Maven build with the working Eclipse setup, focusing on how lombok.config and lombok.log.fieldName = LOG are discovered. Done means the Maven compilation recognizes the configured LOG field as the Eclipse build does.