IRIS Docker template not copying files

Using the Basic template for InterSystems IRIS development environment with Docker: github

If I use the Dockerfile_mini file and COPY a backup, the file shows up.

COPY ./20241104_1448.cbk /home/irisowner/dev 

ARG IMAGE=intersystemsdc/iris-community
FROM $IMAGE

WORKDIR /home/irisowner/dev
COPY ./20241104_1448.cbk /home/irisowner/dev
...

However if I use the Dockerfile with the additional features, the file is copied (via logs) but not on the container filesystem.

Is this a bug?