ROKiT Williams Racing's technical director Paddy Lowe is set to take a "leave of absence" from the team ahead of the 2019 Formula 1 season for personal reasons.
The team missed the opening two and a half days of testing for the 2019 season due to the late completion of the auto, with deputy team principal Claire Williams describing the delay as "embarrassing".
The vehicle was also the slowest on track when it did appear, adding to the woes of a team who finished last overall in 2018 and have not won a race since 2012.
Furthermore, the FIA frowned upon the FW42's unusual curved mirror design as it appeared in pre-season testing, and has compelled the team to change the layout for next week's season-opening race.
Where next for Williams after failed Lowe gamble - F1
It scored just seven points last season amid fundamental flaws with its overhauled FW41.
That increased expectations for the FW42 but also raised the significance of the vehicle in terms of the competence of Williams's new senior structure.
The season starts in Australia on March 17.
Williams said in a statement that "Paddy is taking a leave of absence from the business for personal reasons". The return to a team where he had once played a key role in the successful active ride programme was supposed to set Williams back on the path to the good times.
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