According to Force India's Andy Green, teams are still waiting to receive "quite fundamental" test information on the Halo device which is delaying the final 2018 chassis designs for next season.
Although important details on the Halo have been shared such as the loads that chassis mountings will be subjected to, teams are still waiting for the details of how the load test will be conducted and applied on the head protection device.
This is delaying the process of finalising the specification of the 2018 chassis for teams up and down the grid as the load test for the Halo cannot be conducted without the real Halo fitted.
This is forcing the FIA into coming up with a new method to conduct the load test as they need to find a way to replicate the forces that are put through the chassis by the Halo. These forces would need higher loads than the Halo would be able to withstand.
This delay has frustrated a number of teams, and Andy Green, Force India's technical director, was far from impressed: "The actual Halo that we're going to run has been defined," he said. "But the actual chassis that it bolts to hasn't.
"To try to get a chassis to cope with the sign-off loads that the FIA have imposed is a challenge.
"The Halo that we're going to race can't withstand those loads, so there's no point in using it to do the load tests on the chassis, because the Halo will fail first.
"So, you have to do it with something else, and that's what we're trying to define at the moment.
"Depending on what that something else is will change how you design the chassis, and how strong you need to make the chassis, because it delivers the load in a different way, depending on the geometry.
"At the moment we're missing the details on that device, and it's quite fundamental to the design of the chassis.
"If you fail the test, you can't run."
To solve this issue it has been suggested by the FIA that a physical test should be backed up by finite element analysis which will allow loads to be modelled on the 2018 chassis of each team. This will be a temporary alternative until a physical test will be adopted for 2019.
This plan will be discussed next week in a technical regulations meeting.