dfs.datanode.ipc.address using port 8010 instead of 50020 - why?

[#1]

Using Ambari 2.6.0.0 we are seeing dfs.datanode.ipc.address configured with 0.0.0.0:8010 rather than the documented port of 50020.

The only explanation in source I can find is this: https://github.com/hortonworks/hadoop-release/blob/HDP-2.6.5.3001-10-tag/hadoop-dist/src/win/templat...

For comparison, here is the config in the Apache reference: https://hadoop.apache.org/docs/r2.7.3/hadoop-project-dist/hadoop-hdfs/hdfs-default.xml

[#2]

This is also contrary to the documentation here: https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.6.0/bk_reference/content/hdfs-ports.html