They have no definite information about when the 'full' JCW will be available, they just want you to commit to an order (and a big deposit!) now to stop you buying elsewhere.
Considering how short the waiting lists are for new MINIs now I can see no reason why you need to be placing an order for something now when neither you nor your dealer know anything about the car.
If it was me, I'd keep an eye on the News section here, and then order a car when you know what it's actually going to be, rather than just putting your name on an order slot.