Bitterness concerning posted soldiers before end of conflict (10)

I believe the answer is:

resentment

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'bitterness' is the definition.
(I've seen this before)

'concerning posted soldiers before end of conflict' is the wordplay.
'concerning' becomes 're'.
'posted' becomes 'sent' ('send' can be a synonym of 'post').
'soldiers before' becomes 'men' (I've seen this before. I am not sure about the 'before' bit.**).
'end of' suggests the final letters.
The last letter of 'conflict' is 't'.
're'+'sent'+'men'+'t'='RESENTMENT'

Can you help me to learn more?

(Other definitions for resentment that I've seen before include "offence" , "Bitterness, indignation" , "Ill will" , "Umbrage" , "Annoyance" .)

I've seen this clue in The Telegraph.

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