Is there a way to programmatically set themes for applications?

In v12 both the blog and article applications support application level themes, we can programmatically create these applications but I cannot see a way to set the theme programmatically

The only option seems to involve changing the default theme for these application types in the admin panel

Is there a way to set these programmatically, we have a job which creates groups and the concern is that the default application type theme is not as expected, if an admin changes it for example