https://wccftech.com/fallout-new-california-launch-october-23/

The fan-made Fallout: New California mod will launch on October 23rd (the same day the nuclear bombs of the Great War dropped in-universe), as announced via ModDB.

This total conversion mod for Fallout: New Vegas, previously known as Project Brazil, will be an unofficial prequel to Obsidian’s 2010 game. Fallout: New California has been in development for five years and the remaining time will be used to polish remaining bugs and to add some side quests.