Just weeks before the deadline for finalisation of the 2021 rules, the F1 teams, Liberty Media and the FIA remain at an impasse.
The June deadline had already been postponed to the end of October, as the parties squabble over the details of the major rules shakeup.
The biggest argument is over the restrictive aerodynamic rules, and there is now an eleventh-hour counterproposal regarding 'open source' technical innovations.
The late flurry of activity has F1 sporting boss Ross Brawn frustrated.
"Over the past two years, we've detailed every stage of the development of the 2021 car," he told Auto Motor und Sport. "Why are they sounding the alarm now?"
One theory is that the teams are simply deploying delaying tactics so that Liberty and the FIA have no alternative except to keep the rules the same.
"The technology always converges when you leave the rules stable for as long as possible," said Mercedes' Toto Wolff.
Some argue that the racing in 2019 has seldom been better.
"If someone raises his hand to suggest something, someone else opposes it on principle, because it could be a disadvantage for them," he said.
The rules deadline is October 31.