Yes all schemes are eventually released. As the top post states the carset is currently released at version 1.0. Due to the amount of cars/drivers in this series I plan to release new versions 2 times a year so expect around December the next version which will contain more of the cars. The way the system works is this workflow:
paint car > present publicly (like on this forum) > inject into game > release in next version update (if its been injected into the game). Everything is staggered by several months. So for example the Coors Light #24 car I presented back on May 1st 2022 is about to be injected into the game (aka driver ratings added, starting to race in the series, etc). So when December rolls around and I release the next update it would most likely be included in that version. The carset is almost at 200+ individual paint schemes/drivers many of which fully painted and sponsored so its a very large thing to manage.
I can't even zoom out to show the entire board but I use an issue track program and each paint scheme is track by an individual ticket just to show the scope and project planning I do:
Zoomed out at 25%:
I track everything from what I plan to paint per week, the scheme details, if its an unsponsored car, been presented, completed etc etc
If I say open the #15 Goodwrench ticket you can see I have all the details and its progress:
I only add the cars in NR203 when I am ready to actually have them race since I don't want to have to think about driver ratings and al that (I have a very deep ratings system I want to take with so the cars I hope to be top tier, mid, and low will possibly perform the way I expect. Plus several of the drivers are from my previous series so I want to make sure I transfer their ratings accurately.
Each carset update comes with several bug fixes too. For example little paint details I missed or wanted tweaked along with minor driver ratings. Version 1.1 will list out any of these significant changes as well as update instructions if you were using 1.0.