At the moment that question is at the bottom of the IRS in-basket, but they will probably have some sort of answer by Thanksgiving, provided there are no government shutdowns or domestic terrorist attacks before then. They are promising reminders to employers who pay 941 taxes, but those can be done with tax deposits.  Here is what IRS says about those:

20. Will the IRS issue reminder notices to taxpayers reflecting the total amount of deferred taxes and the payment due dates? (added July 30, 2020)

The IRS intends to issue a reminder notice to employers before each applicable due date. Because each return period is treated separately for purposes of determining the amount of tax due for the period, Form 941 filers that deferred in all four quarters of 2020 may receive four reminder notices stating the deferred amounts that are due on the applicable dates in 2021 and 2022, even though the amounts for all four quarters will have the same due dates of December 31, 2021 and December 31, 2022.

https://www.irs.gov/newsroom/deferral-of-employment-tax-deposits-and-payments-through-december-31-20...