No, they are one in the same chain. Look at the 'getpeerinfo' from one of the clients and you'll see Un-0.10.0 and Un-0.10.1 mixed in with the Pr-0.10.1 clients. They are separate clients, the same chain.
OK, I follow, so I was correct earlier - a new client for the Un testnet "branding" the coins as Prototanium?
So again its not a sidechain it is the testnet chain and has no actual relationship to the Un chain?