Unfortunately HR miscast comedians -- they're employed only once a year (9,5)

I believe the answer is:

christmas cards

'they're employed only once a year' is the definition.
(Christmas cards are sent once a year)

'unfortunately hr miscast comedians' is the wordplay.
'unfortunately' indicates an anagram.
'comedians' becomes 'cards' (I've seen this in another clue).
'hr'+'miscast'='hrmiscast'
'hrmiscast' anagrammed gives 'christmas'.
'christmas'+'cards'='CHRISTMAS CARDS'

I've seen this clue in The Telegraph.

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