Film takes prizes including Best British Independent Film, Best Director and Best Actress.
Actress will receive award at BIFA ceremony on December 2.
Other winners were ‘You Were Never Really Here’, ‘American Animals’ and ‘Early Man’.
Yorgos Lanthimos comedy to compete against American Animals, Beast, Disobedience and You Were Never Really Here.
Other winners include ’Dogman’, ’The Death Of Stalin’, and ’Bergman: A Year in a Life’.
Tentpole is second highest Warner Bros release of all time in China on $147.4m.
UK filmmaker’s follow-up to God’s Own Country is set for March 2019 shoot.
