With the FIA's International Court of Appeal due to convene on Tuesday to rule on whether double-decker diffusers used by the three teams are legal, Byrne has added his weight to arguments that they are not within the rules.
In particular, he believes that the teams' insistence that holes in the floor of the car designed to improve airflow through the diffusers should be regarded as 'slots' goes against what everybody accepted as correct for many years.
Article 3.12.5 of F1's technical regulations states: "Fully enclosed holes are permitted in the surfaces lying on the reference and step planes provided no part of the car is visible through them when viewed from directly below."
The three teams at the centre of the dispute claim that breaks in the floor of their car are not holes, but gaps between the step and reference planes of the car - so exempt from the requirement that no part of the car be visible through them.
Byrne has told Gazzetta dello Sport that he is sceptical about such a suggestion, however, saying teams had never thought like that before.
"It's a rule set at least 14-15 years ago, and that for many years everyone interpreted in the same way," said Byrne, who won many world titles for Ferrari working alongside Ross Brawn. "If you look at the Brawn car from underneath, you can see the suspension."
Speaking about his feelings on the situation, especially going against one of his former close colleagues, Byrne said: "Ross Brawn and I remain good friends, but one thing is personal relationships, another thing is the professional aspect. And I work for Ferrari."