As of 06/27/2018, it appears that most all reservation holders, who had not been invited to configure before that date, have been allowed to configure their Model 3. If you have not received an email from Tesla, you should check your online account because many have reported not receiving email invitations to configure.
The shock for many entering their configurations beginning on June 27th was that the car delivery estimates are now ~3-5 months. It is possible that this 3-5 month timeline is more of a maximum delivery estimate as opposed to an individual delivery estimate. Tesla has historically been very inaccurate in their estimates when it comes to the Model 3. Because of the situation with the U.S. Federal tax credit, it is likely that Tesla has manufactured a large block of Model 3’s that are waiting for July 1st in order to start deliveries. Some of the orders placed today will need to be matched with cars that have already been produced. Until Tesla has a better idea of how many cars of each configuration are being ordered, they won’t be able to give a realistic delivery estimate.
The daily analysis that had been on this page has been discontinued. You can continue to check the community Model 3 spreadsheet for VIN assignments and delivery information, which is now more timely than is invitation information.