There are upgrade paths in line for recent Amigopod/ClearPass Guest buyers to ClearPass Policy Manager w/Guest and OnBoard. I suggest you talk with your local Aruba reps for details and to see if you qualify. If you do qualify you'll be eligible for an upgrade to ClearPass Policy Manager, Guest, and Onboard. The licensing levels will depend on your current Amigopod/ClearPass Guest licenses; but in most cases i you qualify, you'll likely be happy with what you get.
There is a FAQ published on this, but I am not sure if it is available outside of the partner portal, so I'll leave the judgement to share the complete details to the moderators and/or Aruba employees.