In this blog: Model X soon to get a red "Order yours" button.
On April 5, 2016, one of our forum members received an email from Tesla saying "In just a couple of weeks, we'll be opening up orders online and in-store for Model X"...
Information comes in an email about the recent Model X reservation and is а pleasant surprise as "Reserve yours" is soon going to be replaced by "Order yours".
The post includes a lot of screenshots from the reservation process and says the delivery window is September/October 2016.
This means that right now it takes around 6 months to get your Model X and with the recent production ramp up after some Jan/Feb delays we expect the delivery time gets further optimization.
Take a look at the screenshots in this forum topic. It's in Bulgarian, but the pics are in International :).