It is not my discovery of this possible theme in Aickman fiction but someone elsewhere on a discussion forum was propounding it as a theory.
He mentions three stories as support for this theory. I will not steal his thunder so I shall leave others to guess which three.
Then I discovered a 4th story: GROWING BOYS with this quote:
“On the warm, wintry grass before them lay what was left of a human body. / The boys had already eaten their way through most of it…”
And I had said this earlier:
<<I think I see what you mean. Not overt, but an undertaste.
From your post, I imagined him sitting on one of the thankfully dark Aickman Islands … around a campfire, the sounds and smells of roasting wafting…
Some of his stories are also about plastic surgery, I recall. The obvious after-effect?>>
Last Balcony: Essex Serpents and Pier’s Echo 
A possible 5th story with a reference:
“Also in the pantry were traces of proteinous foodstuffs which the hired staff had withheld and taken home to sell.”
from LARGER THAN ONESELF
“No breakfast, no man,” my father had always said.
–from MEETING MR MILLAR
That’s a bit *too* subtle, but Mr Millar in a story that involves supposed
graveyard smells in the building is found hanging from a hook….attenuated as
if the meat had been drained off his body??
Meanwhile, I daren’t explore THE SWORDS in this light!
From ‘The Attempted Rescue’:
“…my Father installed a costly and elaborate system of sewage disposal. The
guileless would be invited to drink from a crystal fountain at the far end of
the vast garden, and after they had confirmed the purity of the water, would be
told that it was straight from the bacteria beds.”
That’s too subtle!
As far as I can establish, however, in this RA autobiography, although there are no direct references to cannibal fantasy , there is evidence that Aickman was interested in Jean Genet’s approach to ‘phantasies’. Genet’s work represented in turn (based on what is said of it) an expression, inter alia, of cannibalism.
This post has now been replaced by the post here giving credit where credit’s due:
https://nullimmortalis.wordpress.com/2010/11/12/john-magwitchs-thesis-on-robert-aickman-cannibalism/
https://dflewisreviews.wordpress.com/2021/09/23/macropsia-and-micropsia-in-free-will/ – cannibalism in ‘A Choice of Weapons’