Green’s Dictionary of Slang

a general excl. of disbelief in or dismissal of an idea or statement.

1963		K. Waterhouse Jubb (1966) 170: Now bugger off! And stay buggered off.
1969		P. Boyle All Looks Yellow to the Jaundiced Eye 158: ‘Bugger off,’ Dermot said wearily.
1975		(con. 1939) J. Rosenthal Evacuees Scene 76: danny: Say it again! philip: Bugger off!
1986		F. Pitt-Kethley Sky Ray Lolly 41: I bite / back the shout of ‘Bugger off!’.
1997		(con. 1950s) J. Byrne Slab Boys [film script] 68: Aw, bugger off!
2003		McGill Reed Dict. of N.Z. Sl. 36: bugger off! ANZ expression of denial or dismissal, as in ‘Bugger off! I never laid a finger on him’.
2018		G. Gilmore Class Act [ebook] ‘You chose the wrong crowd [...] Bugger off!’.
2024		J. Meades Empty Wigs (t/s) 601: ‘Bugger off you little chit!’.