Lord Wilmore posted:

History shows Josiah's death in 609 BC and other sons reigning before Zedekiah (who was only 8 when his father died), but Nephi and his family would likely have not considered those other sons to be true kings, therefore Jeffrey R. Chadwick posits that the first year of the reign of Zedekiah was likely 609 BC and Lehi left Jerusalem in 605 BC.

https://byustudies.byu.edu/content/dating-departure-lehi-from-jerusalem (paywall)