Reporting the recharacterization of excess Roth IRA contributions

In April 2020, I contributed $4000 to my Roth IRA, but I found out while going through Turbotax this year that I'm not eligible to contribute to my Roth. In March 2021, I then contacted my retirement account manager and recharacterized the $4000 contribution and $2000 in earnings into my Traditional IRA (will be nondeductible).  They told me I would receive a 1099R early next year, 2022.

How do I report this for my 2020 tax year without having to wait until 2022 to receive the 1099R to file an amendment? And are there any other forms I will need to file besides my 1099R?

Thanks!
(Edit: using Turbotax Deluxe Windows edition)