GM expects to build 400,000 electric vehicles (EVs) in North America from 2022 through mid-2024 and increase capacity to 1 million units annually in North America in 2025. Reuters reported in April GM is considering building at least two additional EV plants on the top of the first four to meet future EV demand.
https://news.yahoo.com/finance/news/indiana-confirms-gm-sdi-build-113720042.html