No clue yet. They are filming now.
The program is due to return to air this spring on BBC One but they don't have any release dates announced yet. It will be Series 32. The prior series just ended airing in late December so there will be a gap I'm sure. It might even be April/May, there's no indication yet and no announcements have been made.
https://www.bbc.co.uk/programmes/b006mj59
They announced last year that from Series 33 on, they will be operating out of new offices at the BBC Studios Bristol, rather than from the main BBC production offices at Television Centre (London). I don't know whether that's strictly starting with Series 33 or if they are making the change early this year in a general way. Either way they will still be using the Dunsfold Aerodome for test track sequences.