This Reuters article makes it very clear that the figure discussed is over 1b, and uo to 75% of the capital costs, so I don't think anything has changed, although the initial headlines stated 1 billion. Perhaps this is why the SP faded till close? Also likely because the indexes faded from green to red. 

Sept 29 (Reuters) - Lithium Americas (LAC.TO) is in talks with the U.S. Department of Energy (DOE) to secure more than $1 billion loan for the Canadian miner's Nevada project, according to a source familiar with the matter.

https://www.reuters.com/legal/litigation/lithium-americas-talks-with-us-energy-dept-secure-over-1-bln-loan-source-2023-09-29/