Formula 1, the FIA and the teams have formally agreed to run the single pre-season test in Bahrain on March 12-14.
In the interest of cost saving, testing has been restricted to just three days in 2021, which means one and a half days of running for each driver.
The test was originally expected to be held in Barcelona on March 2-4.
However, as soon as it became clear some weeks ago that Australia would be postponed and Bahrain would become the opening race, teams agreed that it would be logical to hold the test at Sakhir, rather than go to Spain.
Avoiding Barcelona guarantees good weather for the test as well as avoiding any COVID restrictions that might be in place in Spain.
With the Australian GP now officially moved from March 21 to November 21, the season will start with the Bahrain GP on March 28.
The test will take place on a Friday to Sunday, two weekends before the opening event, with 11 free days before the cars take to the track for FP1 in Sakhir.
There was a debate about holding the test on the weekend before the opening race, on the date originally reserved for Melbourne.
That would have required a change to the FIA sporting regulation that specifies that the test has to take place at least 10 days before the first event.
Most of the teams were happy with that, because it would give them an extra week before cars and equipment had to be shipped out, and it would reduce accommodation costs.
However McLaren, the only team to change its engine supplier over the winter, was opposed to the idea, as the team wanted to keep the normal interval in order to have time to properly assess its new package. It's understood that F1 was also keen to maintain a two-weekend gap.
The change has an impact on car build schedules for the teams. With the original Barcelona test schedule they would have had to have take their new cars to Spain on around February 28.
The cars now have to be ready to fly to Bahrain with the rest of the equipment on March 4-5.
However both race cars – and a spare chassis – now have to make that date, whereas previously the second car would only have to be ready to fly to Melbourne a week later.
This is the first time in the modern era of restricted testing that there has been no official running in Europe before the first race, although teams will still be able to conduct 100km filming days at tracks of their choice before their cars are flown out, if they have time.
They can also potentially hold filming days in Bahrain in the days after the test.
Bahrain last hosted a full pre-season test in 2014, which was the first season of the hybrid rules. However, it followed an initial session at Jerez.
The choice of Bahrain creates obvious logistical challenges for the teams, as the venue is much further away from base than the usual winter venues in Spain, and it will be harder to fly parts back and forth.
However teams will benefit from the fact that all their freight and garage equipment can stay in Bahrain, and mechanics will potentially be able to work in the garages during the break before the first race.
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