Some Formula 1 teams look set to resist the push for any aerodynamic changes to improve overtaking in 2019 that will have to be agreed in the coming weeks.
The subject, which will be discussed in Tuesday's F1 Strategy Group meeting in Paris, came to the fore after there was a lack of overtaking in the Australian Grand Prix, and it was discussed by the FIA, F1's chief technical officer Pat Symonds and team technical bosses in Bahrain.
There was no consensus in that meeting, and discussions will now move on to team boss level at the Strategy Group.
In theory, the deadline for any technical regulation changes for 2019 is April 30, although they can be made after that date with a unanimous vote of the teams.
However, with teams voicing concerns about the principle of the changes, the timing, and the potential cost, that may prove hard to achieve.
"I think the question first of all is what is the strategy behind it?" said McLaren racing director Eric Boullier.
"Is is just for overtaking, and is it a knee-jerk reaction after Australia? In Australia there was a lack of overtaking, but actually Bahrain was one of the best races for the last decade.
"If it's a reaction to Australia, that's maybe a bit too fast and in a hurry."
The team of researchers is working under Symonds on honing the 2021 F1 rules package has also been helping FIA technical boss Nicolas Tombazis with an investigation of what changes could be made for next season to help drivers stay closer to the car ahead.
Research has indicated that "out-washing" front wing endplate elements designed to control the airflow around the front wheels also have a detrimental effect on the following car.
Along with a bigger rear wing flap and more powerful DRS, removing those elements has been proposed as a way of improving overtaking chances over the next two seasons of the current regulations, before the 2021 package is introduced.
Boullier cautioned that teams could be forced into making a series of changes over the next three seasons.
"I know there is a working group on the FOM side, under Ross Brawn's experience and guidance, to work and to address this concern for the future of F1 from 2021," said the Frenchman.
"So my question is, should we address this and take a decision in less than two months, and change radically the F1 aero platform or aero regs with the risk that we maybe have to change it again in 2020, because it's not doing what they wanted or expected to achieve? And then change again in 2021?
"If we change the regulations three years in a row, obviously this is very costly, and I don't think that this is where F1 needs to be when we are talking about sustainability, cost-saving. Why not standardisation or prescription on some parts of the car?
"I think we should investigate this more to try to build the future of F1 and leave the aero like it is so far until we have a better idea of what we want to achieve in 2021."
Force India technical director Andy Green believes that it is already too late to make big changes, and he's anticipating that the rules will stay as they are.
"I think it is more than likely," said Green. "It is pretty much unprecedented to have a rewrite of the technical regulations in the middle of April for the following year.
"Time is a big factor, yes. But also trying to understand what changes need to made is another one.
"Everybody is assuming that the changes proposed help the car following, and help overtaking. Well, that is a big assumption. There is no data to prove it, it is only someone's idea."