Heartless pal during year out circulated impersonal email (9)

I believe the answer is:

autoreply

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'heartless pal during year out circulated impersonal email' is the definition.
I can't judge whether this defines the answer.

'heartless pal during year out circulated' is the wordplay.
'heartless' suggests removing the centre.
'during' means one lot of letters goes inside another.
'circulated' indicates anagramming the letters.
'pal' with its centre taken out is 'pl'.
'year'+'out'='yearout'
'yearout' is an anagram of 'autorey'.
'pl' placed inside 'autorey' is 'AUTOREPLY'.

Can you help me to learn more?

(Another definition for autoreply that I've seen is " prepared comeback".)

I've seen this clue in The Independent.

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