Considering this announcement was made earlier today by the IRS, if implemented in the program this change would not be immediate. However, the IRS does have instructions for those who have already filed:

"Taxpayers who have already filed for tax year 2018 but qualify for this expanded relief may claim a refund by filing Form 843, Claim for Refund and Request for Abatement and include the statement “80% Waiver of estimated tax penalty” on Line 7."

While the program remains coded for the prior underpayment percentage, you should have the ability to override the penalty amount to the 80% should you wish to do so.