Now, if by "first wave or two of people" you mean people who are not employees and will be in the first group of Model 3 deliveries, which are reservation holders who are currently Tesla owners and who live on the West Coast of the US, then I agree that those people may not be offered a personal inspection and/or test drive of a Model 3 before they finalize the configuration of their car.
However, because by the time that public group needs to configure their 3 at least 5,000 cars (my personal estimate) will have been produced and delivered to employees, which will likely take several months to accomplish (since production ramp up will not go from zero to 1,000/week in just a few weeks, it will take months, i.e. "more than one month") so it seems possible that by that time Tesla may well provide 20 to 50 new Model 3 vehicles to West Coast showrooms.
The latter scenario is the one that I think is more likely.