You will find the date field in Form 1116, Part II, column l (for Larry). 12/31/2020 works for most people but another poster is reporting "1099 taxes" also works.
In form 1099-DIV, Box 8 has two blank lines -- if both are "RIC" and the check box is checked, life is good. Then move on to your Form 1116 and make sure the date field has a valid date (a bit surprised that 1099 Taxes works, but hey, if it does then it worked for at least one person).
