But French tango innovators Gotan Project beat her to the title of best newcomer.
It comes 13 years after he won best newcomer at the event, which was aired on Channel 4 on Wednesday night.
The film was premiered at the BFI London Film Festival last year, where El Hosaini also won a best newcomer prize.
The best newcomer award went to 18-year-old east London MC Chipmunk.
There were also screams and chants for Kosovo-born, London-raised pop star Rita Ora, whose three UK number one singles this year helped her to the best newcomer crown.
Comedian and TV host Henry, one of the founding figures of Comic Relief, enjoyed recent success with his theatre debut as Othello - for which he won best newcomer at the London Evening Standard theatre awards.
Daniel Simonsen was named best newcomer.
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The duo won the vote for best festival pop act, best live newcomer and anthem of the summer for That's Not My Name.
Sally El Hosaini, director and screenwriter of My Brother the Devil, was named best British newcomer in recognition of her London-set family drama.
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The Grierson Award will be given to the best documentary while the inaugural best British newcomer award for writers, producers and directors will also be presented at the ceremony, which will be hosted by Paul Gambaccini.
Most of the awards are decided by a judging panel, but three awards are voted for by the public: Best British Video, Single and Newcomer.
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Paul Laverty is nominated for best screenplay, while actor Paul Brannigan is up for most promising newcomer, for his portrayal of a Glaswegian father.
Marlon Byrd had a pair of RBI singles and fellow Mets newcomer John Buck was in the middle of three rallies as New York improved baseball's best opening day record to 34-18 despite dropping its first eight openers.
Marlon Byrd had a pair of RBI singles and fellow Mets newcomer John Buck was in the middle of three rallies as New York improved baseball's best opening day record to 34-18 (.654) despite dropping its first eight openers.
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