Formula 1 stewards have explained why Sergio Perez has avoided a 10-second time penalty before the Qatar Grand Prix after his chassis change.
In the Sprint race, Perez's Chassis 01 was "damaged beyond repair" according to stewards and so the team began to build up Chassis 02 for the Mexican to a level which would be deemed as having a third car available to the team - something prohibited under the regulations.
In Japan, Williams was found guilty of breaching this rule with Logan Sargeant who was forced into a pit-lane start and an additional 10 second time penalty during the race.
For the chassis change, and a later complete power unit change, Perez will start in the pit-lane, but will not serve the 10 seconds that Sargeant did at Suzuka.
The team dismantled the car to such an extent that it was not considered a car anymore under Article 27.2 of the Sporting Regulations, with the dismantled parts and survival cell being covered in accordance with Article 40.6.
Only then, did Red Bull start to build up Chassis 02 for Perez, and so a strict reading of the rule book suggests that the team did not have more than two active cars ready.
The build-up of Chassis 02 was done without FIA supervision and with the specification of parts changed which required the pit-lane start.
As such, no additional penalty was issued by the stewards to Perez - although the stewards did note that Red Bull's interpretation of the rules "might not be fully in line in the intention" of the regulations, and made a recommendation for the issue to be discussed within the Sporting Advisory Committee.