Your reservation will determine in what order you are invited to configure. When you configure, you will be presented with different performance options and configurations. They will probably have different delivery dates based on what the factory produces first. I had an early reservation on the Model X, but have been pushed back significantly because I didn't want to order the Performance version. The good news is that means I get a more perfect car with a lot of early problems discovered and fixed before mine is produced. Same as other car makers. For example, I believe Porsche Macan customers that didn't want to pay for the higher performance versions had to wait around a year longer.