My opinion is that a smaller package will be passed in January / February. I think the smaller package will include climate change related issues, including some kind of EV tax credit. It will still be effective 1/1/22.
A bigger unknown is that the current House version of BBB does income tests on the prior year as well as the current year (in the case of taking delivery in 2022, they would evaluate you on 2021 and 2022 income) - if EITHER one is over the designated limits, it will reduce the credit you receive. Will they keep the 2 year income test? What will be the phase out limits? These are unknows...