This species is on the current ACT rare plant list having been included in the latest revision in (2015-2016). It was orginally thought to be quite rare locally occuring only on Black Mountain sandstone. Since its inclusion on the list, there have been a signficant number of new locations that have been discovered away from black mountain including some quite large populations.
With the current distribution in mind I'd actually consider this species to be relatively common. It should be removed whenever the list is revised next, and the CNM status should reflect this (though I can't change that at the moment).