The Model 3 will be revealed tomorrow at 11:30AM but you can preorder it for $10,000 at the Tesla store in TML tower and the pulse when they open tomorrow or on the Tesla website. From what I've heard, there were over a 100 people at the Tsuen Wan store today.
Nothing about the Model 3 is known other than its name, so the unveiling tomorrow is the first time anyone has seen it.
More info here: https://www.teslamotors.com/en_HK/bl...erving-model-3
Apparently, tomorrow is only "Part 1" of the unveiling of the Model 3, and "Part 2", which is where things get interesting, will be unveiled close to the Model 3's production date next year.
Most likely we're going to be seeing something that closely resembles the final form of the Model 3 tomorrow, but just like the Model S and X, they're going to be adding things to the car up until the date of production.