Bostock fifth, while Holden takes fourth in women's race
Mark Cavendish has won the British National Road Race Championship for the second time in his career.
The Manx Missile sprinted to victory in Castle Douglas, having found himself in a five-rider break for much of the race.
Fellow Manxman Matthew Bostock was also in contention until a crash in the closing stages, finishing fifth overall.
Earlier in the day, Lizzie Holden secured fourth in the women's race, adding it to her third place finish in the time trial event.
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