Some owners report that you can't use the app for an appointment since your car is not registered as owned by you for the first 7 day refundable period.
It goes beyond not being able to use the app for an appt for me. I can't make an appt period because the SC told me they won't work on a car that I don't own. That approach makes it hard to use the 7 day refund period if you can't find out if Tesla will fix issues you are having, and one thing Tesla excels at is having initial quality issues.