Like, you're supposed to close the books on December 31 just so you can make a payment that date?  Particularly difficult for people who own mutual funds with capital gain distributions in late December.  Or those who visit family between Christmas and New Years Day.  Another jerking knee.  Meanwhile, 

Senator Mike Crapo, chairman of the Senate Finance Committee, and Senator Ron Wyden, the committee’s ranking member, jointly released a discussion draft of a broad and sweeping bill titled the Taxpayer Assistance and Service, or “TAS,” Act. The draft bill runs 163 pages and contains 68 provisions – about 40 of which reflect National Taxpayer Advocate recommendations.

One of those provisions:

Sec. 903. Quarterly Installments for Estimated Income Tax Payments by Individuals.
Estimated tax installment payments for individual taxpayers are called “quarterly payments,” but they are due at three-month, two-month, three-month, and four-month intervals (April 15, June 15, September 15, and January 15). This is confusing to taxpayers. The provision would revise the estimated tax payment deadlines so they fall at even quarterly intervals (April 15, July 15, October 15, and January 15). It is effective for installments due in taxable years beginning after the date of the enactment.

https://www.taxpayeradvocate.irs.gov/news/nta-blog/senate-finance-committee-chairman-crapo-and-ranki...