Perhaps 2001: A Space Odyssey ultimately used up Kubrick's focus (4)

I believe the answer is:
year
'perhaps 2001' is the definition.
I can't tell whether this definition defines the answer.
'a space odyssey ultimately used up kubrick's focus' is the wordplay.
'ultimately' suggests the final letters.
'used up' shows that the letters should be reversed in order (in a down clue, letters go up).
'focus' says to take the centre (focus can mean the centre of something).
The centre of 'kubrick' is 'r'.
The last letters of 'space odyssey' are 'ey'.
'a'+'ey'='aey'
'aey' backwards is 'yea'.
'yea'+'r'='YEAR'
Can you help me to learn more?
(Other definitions for year that I've seen before include "12 months" , "Period of just over 52 weeks" , "Twelvemonth" , "TV advert" , "Manage" .)
