Silly fellow getting time and support accepted (4-5)

I believe the answer is:

bird-brain

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'silly fellow' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'time and support accepted' is the wordplay.
'time' becomes 'bird' (both are slang for a prison sentence).
'and' says to put letters next to each other.
'support' becomes 'bra' (a support for the breasts).
'accepted' becomes 'in' (I've seen this in other clues).
'bird'+'bra'+'in'='BIRD-BRAIN'

'getting' acts as a link.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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