it will be not only on paybase the 20$ range price because we all will buy paycoins from other exchangers and go to paybase to convert them into fiat or btc... and the amount of paycoins from th merchants will get lower they will have to rise the price up to keep the xpy exchange running
Why would people sell for a loss on the exchanges when Paybase opens? Or are you saying that the faithful will pay any price up to "$20" for coins on the exchanges before Paybase opens?
Then if that is the case, if the sellers were to move the market themselves, they could price the coin near "$20" and force the buyers into their neighborhood. Not everyone will want to do that and many will just want to liquidate their position if they strongly want out.