EL expression to restrict springboard group to a specific hierarchy

Summary

EL expression to restrict springboard group to a specific hierarchy

Content

We are trying to let users have access to dashboards directly from the springboard.

I need the specific EL expression that can restrict visibility of the group/tab only to the direct and indirect reports that roll up to the VP of HR. The idea is to do a pilot launch for a specific group of users.

Has anyone succeeded in implementing similar requirements? Or does any one have documentation that can help?

Thank you!