I don't think it will be soon, it must be need to some time because I don't think they don't need central bank.
it will be happend in the future but we all dont know when this will happend.
Even for the long run though I'm not sure the bank system will be replaced, the bank is not only a place to save money for many people dude ? but many other functions, such as borrowing funds, controlling currency circulation and many others, I'm not sure the bank will be replaced by another system?