The reason Mercedes is up in arms about the rear wings is that they are technically illegal, although FIA tests have been unable to prove as such.
Article 3.8 of the FIA's technical regulations states: "Any specific part of the car influencing its aerodynamic performance must remain immobile in relation to the sprung part of the car."
In order to deal with this, the FIA puts cars through strenuous tests with a given allowance for the amount any aerodynamic part can flex.
Article 3.9.6 demands: "The uppermost aerofoil element lying behind the rear wheel centre line may deflect no more than 7mm horizontally when a 500N load is applied horizontally."
These tests are being altered from the French Grand Prix onwards but that is not quick enough for Toto Wolff or even Aston Martin team principal Otmar Szafnauer.
"To design something that flexes just the right amount and to pass the tests but still flex, takes a big effort," said Szafnauer. "But to design something that is stiff doesn’t take effort at all and it can be done very, very quickly.”
Red Bull isn't the only team affected
So the big boys are arguing but the fallout has serious ramifications throughout the grid.
In a budget cap era that has already seen Mercedes withdraw from Pirelli tyre testing after surprise expenditure in the wake of Valtteri Bottas' heavy crash in Imola, this could be strategy-changing, especially with the 2022 regulations lurking over each technical director's shoulder tempting them into switching to 100% focus early.
With the potential power of the wings down the two long straights at the street circuit, where it has been estimated Red Bull could have an advantage of six-tenths of a second per lap. this story is far from over.