Has PVR now become a "right"?
PVR is a right. Try keeping someone in who wants out! It doesn't happen. This isn't the 1950s.
As far as I know, no-one in recent times has been kept in beyond 12 months within recent memory, with the exception of a RAF NCO whose PVR was rescinded pending a court martial - he won his case in Strasbourg although this was to do with the CM rather than the PVR. There are two cases I recall reading about - an Army officer and a RN senior rate - who wanted out earlier than the notice period but whose applications were refused, and who went to court. They were unsuccessful.
So, you may need to do the time but you will get out.