Red Bull has requested formal clarification from the FIA about whether it is now free to test a 2011, or even a 2013 Formula 1 car, following the Mercedes test affair.
Amid a renewed focus on testing restrictions following the FIA International Tribunal hearing into Mercedes' running of its current car after the Spanish Grand Prix, Red Bull wants to know more about what is and is not allowed.
AUTOSPORT has learned that in response to a request from the FIA for teams to now give formal notification of test plans, Red Bull team principal Christian Horner has written to F1 race director Charlie Whiting asking for further details about testing limitations.
In the letter, Horner has asked for Whiting to specify whether there are circumstances under which Red Bull could participate in a Pirelli test with its 2013 car if certain conditions were met - as were originally laid down to Mercedes in correspondence with the FIA prior to its own test.
He also questions the exact procedures for approving the tests, as well as whether or not the team needs formal approval from the FIA's World Motor Sport Council, as was suggested in the Tribunal hearing.
Furthermore, in light of it emerging that Ferrari had conducted two Pirelli tests - one in 2012 and one before this year's Spanish Grand Prix - with full FIA approval, Red Bull wants to know if it too can run a 2011 car at tracks shortly before grands prix are due to take place.
In particular, it wants the FIA to clarify whether an unlimited mileage test at a venue prior to it holding a grand prix, conducted by race drivers, using a 2011 car that 'conforms substantially' with the current rules, is OK.
This is in reference to Article 22.1 that outlaws testing undertaken by a competitor with a car from the current year or previous year, as well as those that 'conform substantially' with the current technical regulations.
Red Bull sources have indicated that the letter is not an attempt to challenge the recent ruling - or open the way for it to conduct 2011 car tests before each grand prix - but simply a way to clarify what is and is not allowed so it knows the situation.
PIRELLI PLANNING MORE TESTS
F1 tyre supplier Pirelli has two further private tests planned over the next month as part of its preparation process for 2014, and has invited all teams to take part if they wish to do so.
Pirelli motorsport director Paul Hembery said that there had not been much interest from teams in the test, while further clarifications were sought from the FIA.
"There hasn't been a huge take up - although there are a couple of teams that have asked," he said.
"There are some clarifications from the FIA, Red Bull being one of them, asking clarification on what terms you could run and what car you could run - and does it have to go to the WMSC to get approval.
"We are all asking for clarification about how that can happen.
"In two weeks' time we are in Paul Ricard and two weeks after that we are in Barcelona. All the teams are invited to that - either to do 1000km, which nobody is coming to, or send an observer, which a few teams might send somebody along to."
Subscribe to Autosport Plus
Register for free