The reason is that you can now buy BTC with RMB from banks (supposedly not possible since 2013).
If you understand the issues of "capital control" it is not hard to see why this would push the value of BTC up.
(the real question is how long until they "ban purchasing" again)
they will ban bitcoin again once they see cash is flowing from china into other parts of the world. i hope they will be a bit more friendly towards bitcoin and embrace it instead of fighting it.