Where in the U.S. are you? If you're in the northeast (as if, SNE or SDC territory), then I could see where your dealer may not have the information. The rest of us have had this information since the middle of February, when orders opened. (I did my first order literally two hours after they opened - I had noticed the pricing announcement, but missed the orders opening announcement, so my managers asked me why I was waiting. Called all my customers right then, first couple was in PDQ.)
And there is no Late May / early June delivery. First orders are for July delivery. And we're all sold out of those, so we're now taking orders for August. (And those will be gone by mid March for us, I expect, so then we're on to September delivery.) I anticipate that they will start actual production in late May, at a very slow tack time while they're making sure the bugs are worked out, and then ramp it up to full speed after about a week. And even if a car is built the first week of June, it still takes up to 3 - 4 weeks for it to actually get to the dealership, due to rail and truck freight times. Once things get fully going, I expect we'll see the standard 7 - 8 weeks from date of order until date of delivery ... but first, we'll have to supply the initial demand, and that is going to take a LONG time.