Setting tlVersionIntroduced on a project

Is there a way to set tlVersionIntroduced for a subproject in a multi-project build? My use case is that I'm adding a new subproject to a multi-project, which causes versionPolicyFindDependencyIssues / mimaPreviousClassfiles to fail, since this subproject was never published before (no previous classfiles / artifacts exist). tlVersionIntroduced seems to be what I want, but that's set on the build - not project - level.

Skimming through old issues here, I found https://github.com/typelevel/sbt-typelevel/issues/57, which suggests it used to be configurable per project, but was changed to be a build setting.

I'm currently doing

    mimaPreviousArtifacts := (
      if (tlBaseVersion.value == subprojectIntroducedVersion) Set.empty else mimaPreviousArtifacts.value
    )

to achieve what I want, but I wanted to double check if there's some other mechanism I should be using for this?

Start by tracing how tlVersionIntroduced, versionPolicyFindDependencyIssues, and mimaPreviousClassfiles are defined and scoped in the sbt-typelevel build. Compare the current build-level setting with the per-project behavior discussed in issue 57. Done means establishing whether a subproject-specific introduction version can be supported without breaking existing multi-project version-policy checks.