The notice (via tesmanian.com), is that Tesla is now in touch with customers:
"Tesla delivery specialist will contact Model 3 owners within a week of the notification to confirm the following:
- Requirements for the installation of home chargers and fees
- Vehicle registration info for the reservation holder’s Model 3
- The Model 3’s loan and insurance—if necessary
- The second payment and remaining balance payment
- The delivery location and date"
It's not clear how many Tesla Model 3 might be delivered by the end of December, but we assume that a three-digit number is a worst-case scenario with a low four-digit number most likely. Not bad, considering that a year ago there was just an empty field.
In comparison, Tesla is expected to deliver more than 100,000 cars in Q4'2019.
Five-digit sales (at least 10,000) will be possible from Q1, as the production rate is already estimated at above 1,000 a week.
The production run consists of three colors: Midnight Silver, White and Blue.