UPDATE: To bypass the payment date of 4/15/2020, you can select "Pay by check" for making your payment. Then make payment on or before July 15, 2020 either by check or by electronic payment to the IRS. "Direct Pay" is one easy way to pay electronically. Here's a link for payment options for the IRS:
https://www.irs.gov/payments
For now, TurboTax won't allow a payment date past 4/15/2020. Please follow the information here to stay updated on changes in the program.
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