Updated my order with FSD before the 1k hike and it seems I still have the same RN number. But I did receive an email from Tesla about the change.
I don't think being "early" means a whole lot with Tesla. Just look at the Y roll out... First Day reservation holders with no cars long (months) after deliveries started. Not to mention people ordering and getting cars assigned/delivered within days... I think spec, location, shipping / transport schedules, and production batches matter much, much more than "First!" Get what you want, when you want it and don't worry about it. ẞ
How fast you get it will likely depend less on when you ordered, and more on model and distance proximity from Austin.
I changed from dual motor to triple motor and did not get a new RN. After waiting for my M3 and an E bike I have become a patient person.
I ordered a Model Y to keep me happy while I wait. Will sell the expensive X although I love it and will miss it. Cannot justify twice the price for a car that largely sits in the garage during COVID.
You'll have plenty of time to add it later. If you check you order number on the list you may be as surprised as I was. I thought I was early in the cue, having ordered a week after the Cybrtrk was introduced. Well, I am 270,000 something with a delivery date in April of 2023. By then the new version may fly and not need FSD.