Agenda item in a letter one's put in post (9)

I believe the answer is:

appointee

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'one's put in post' is the definition.
I can't judge whether this definition defines the answer.

'agenda item in a letter' is the wordplay.
'agenda item' becomes 'point' (I can't explain this - if you can you should believe this answer much more).
'in' is an insertion indicator.
'letter' becomes 'pee' (the letter P).
'a'+'pee'='apee'
'point' going into 'apee' is 'APPOINTEE'.

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(Other definitions for appointee that I've seen before include "Chap getting post" , "One assigned to a post" , "has been given a role" , "Job-holder" , "chosen candidate" .)

I've seen this clue in The Telegraph.

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