I have not verified this issue, but this is a great workaround if TT correctly calculates estimated payments, but not the application of refunds.
One thing to note is that the IRS does not generally care about the specific date, everything is broken up according to those dates in the columns. So assuming you filed last years return on time, your applied payment simply needs to be listed in the first reporting period of 2021.
With changes like this, of course, we have to watch out for unintended impacts. As stated, this fix does not include backing out the applied refund somewhere else. As a result, if there is some other form that includes it, there might be an error there. An example might be the calculation of how much you paid in total taxes as a credit on a state form. Again, I have not verified this, just discussing possibilities to watch out for.
