A client's twin children turned 17 years old in December of 2020, making them ineligible for the $2,000 child tax credit per kid.  They will get the additional child tax credit of $500 per kid.   

Question:  The new American Rescue Plan increases the age to 18 for the child tax credit, but does that apply to 2020?  I thought the child tax credit changes included in the new stimulus bill are effective for tax year 2021 - so anyone with a child that turned 17 in 2020 is just out of luck?