The FIA has confirmed that Abu Dhabi and Hungary will complement Bahrain in this year's in-season group test schedule.
Bahrain will kick off the in-season sessions on April 18/19, but Hungary has come about as a switch from Silverstone, and will take place on August 1/2.
Teams will have a free agenda at these tests, but will have to run young drivers who have competed in fewer than three Grands Prix on two of the four days.
Abu Dhabi will once again host a post-season test on November 28/29, but for "the sole purpose of providing all competitors with the chance to test the tyre specifications to be used the following season," according to the governing body.
Pirelli will therefore trial its 2018 compounds before the December 1 extended deadline set by the FIA yesterday.
F1 2017 group test plans
Barcelona Feb 27 - March 2
Barcelona March 7 - March 10
Bahrain April 18 - 19
Budapest August 1 - 2
Abu Dhabi November 28 - 29
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