Sadly the hunt for the secret source code VIN became a preoccupation for folk who ordered Model 3s precisely because of the lack of info from Tesla. The joy of discovering one is akin to your first born, a time of heady enlightenment and cause for celebration. BUT VINS can change and disappear completely. The shock and loss causes immeasurable heartache and this forum is rife with tales of VIN stripping. There is however an exciting new search for you - the final invoice. I say final but actually you can have several final invoices but anyway that should be the next thing but not always. You may receive an email from Tesla saying they are working hard to deliver your car or words to that effect. Don't be tempted to reply as the lack of response from them tends to invite further depression. Ship movements become interesting. YouTube videos of varying quality on TACC become fascinating. Obscure EV charging RFID cards start to arrive with every plop of the letterbox. You may, not always, depending on how well organised Tesla are, receive an email notifying you of your planned delivery date. This is always the least convenient date for you, especially chosen to conflict with your holidays, your sister's wedding/funeral, railstrikes and bad weather. Do not even attempt to change it at this stage. You will receive a phone call from Steve/Rob/Nigel/Algernon from Tesla (BTW I made up Algernon) about a week or so before delivery confirming the date. Now is the time to pump him for information. Most people are in shock however and just manage to mumble a few platitudes. It is useful to have a partner with you during this period as he/she can ask why you have agreed to collect the car from Edinburgh when you live in Sussex. It's those little details that can so easily be overlooked.
Finally the registration. This is secret. This will only be revealed to you at the last possible moment, literally hours before delivery.
So you see this wonderful journey you have embarked on is full of ups and downs, setbacks and joyous moments that you will treasure for a couple of hours. It is a journey that many have travelled and you can rest assured that your own trials and tribulations have been experienced by every other Tesla Model 3 owner. Enjoy.