Hello guys,
Pilot43, I exactly confirm what says Scagrams as I made the assessment too, for now it is opened for eastern country only. So yeah it's not write on their web site, because initially WizzAir planned to take anyone.
In my case I succeeded the assessment with BAA, and they told me that they're a little embarrassed with the WizzAir's new directive, but for now they have to deal with that.
However, I don't think WizzAir could find only eastern pilots by February, so maybe that people like me who succeed assessment may (I said MAY) be call by February.
Therefore BAA can't confirm this, they absolutely don't know what will happen, they are still waiting for information from WizzAir at this time.