Label group migration - existing files labelled with former parent labels

Hi,

I have a question about behavior during migration from legacy parent labels to label groups.

Historically, we were allowed to apply parent labels directly to content. In our environment, we have an existing parent label called PUBLIC which has sublabels. PUBLIC itself has content encryption configured, so during migration it will be recreated as a sublabel within a label group.

As a result, there are existing files that are currently labelled simply as PUBLIC (applied back when parent labels could be used directly). Post-migration, we plan to de-publish this newly created PUBLIC sublabel from user-facing policies.

My question is about what happens to those existing files during and after the migration. Will files that are already labelled as PUBLIC automatically be updated to a specific label within the label group, such as PUBLIC/PUBLIC, or will they remain labelled as PUBLIC with no automatic relabelling?

In other words, does the label group migration perform any automatic relabelling of existing content, or does it only affect label structure and publication going forward?