I filed early just to get it out of the way, if the child tax credit goes up, will I not get it now ?

[SweetieJean]

We don't know if the CTC will go up, or even if it will be retroactive for 2020 if it does.  It's only in talks right now. There is no bill in Congress as of yet.

[DawnC]

No, but the Child Tax Credit is unlikely to change for the tax year 2020 - it is up to $2000 (it has been $2K since 2017).   If you need to change anything on a return you have already filed, you would need to file an amended return once the original return is processed.    If your tax return gets rejected for any reason, you can make any changes needed before you re-submit it, but once the IRS accepts your tax return - changes have to be done through an amended return.