Renault has revealed its aero development progress since Formula 1's summer break was hurt by it needing to put its windtunnel out of action for several weeks for an upgrade.
The team has faced difficulties getting on top of the aero characteristics of its car, with the RS.19 having not produced the kind of step forward that had been hoped for.
Renault F1's managing director Cyril Abiteboul said what the team learned about the car in the first half of the year prompted it to decide it needed to improve its Enstone windtunnel, which meant putting it out of action for nearly one month.
He explained that the team had accepted it would have to take a hit on the windtunnel at some point, especially with the major 2021 rule changes just around the corner.
"We know the problem," Abiteboul told Autosport.
"The front wings are super-sensitive, the way that they are hitting the bodywork, hitting the floor, leading edge and so on, they are super-sensitive and we have understood a lot in the windtunnel.
"This meant the windtunnel was shut down for more than just the [summer] shutdown.
"That impact on development and the fact that we were working on multiple projects meant that we were delayed, but that was investment.
"If we want to be at the level we want to be ultimately, we had to do these things. So it is an encouraging sign of things to come.
"But there is so much more to be done so I prefer to keep my head down."
Abiteboul explained that the tunnel was closed both sides of the shutdown, and it needed an upgrade to bring it up to spec having not had enough investment put into it under the team's previous owners.
"It was started before and was completed after [the summer break] so it meant we lost almost a month where we had absolutely no windtunnel usage," he said.
"It was planned, and was the sort of thing that goes back to the previous ownership because very little investment was done and it is something that we were pushing back, pushing back, pushing back, but at some point we had to do it.
"With 2021 coming very near, we needed to be ready with everything, even if it meant sacrificing some of this year's development."