Refresh from prior year to complete extension return

I had to make an amendment for 2020 (TT 2020 Premier-Mac) concerning cost basis which changed by capital gains/loss.  In the mean time I filed an extension for 2021 (TT 2021 Premier-Mac).  I have completed the amendment for 2020 and assume that I need to refresh my 2020 data into my 2021 return.  Per research, I see that Capital Gains data is part of the transfer process.

Can I refresh my 2020 data into my 2021 return that was already started and an extension was performed?  I hope that I do not have to re-do any new data already entered for my 2021 extension.