Hurriedly add policy — no getting upset! (4,2)

I believe the answer is:

tack on

'hurriedly add' is the definition.

'policy no getting upset' is the wordplay.
'policy' becomes 'tack' (as in the phrase 'changing tack').
'getting upset' says the letters should be written backwards.
'no' reversed gives 'on'.
'tack'+'on'='TACK ON'

(Another definition for tack on that I've seen is " Affix by stitching".)

I've seen this clue in The Times.

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