I agree with jDk and as I have said before ptcl can't really block vpn's. The only viable solution would be to filter and block each and every vpn server by their ip address and each vpn provider fields lots of servers, then there are hundreds of vpn providers.
Filtering and blocking them all would require substantial resources that I am sure ptcl is not interested in investing and then there are new servers opening everyday. They still haven't managed to block all p0rnsites just because there are so many.
If they block most usual ports that most vpn run's on then just use a vpn that you can route to another port manually (Hotspot shield don't allow that as far as I know).