Benefit completely will stop, in distressing fashion (9)

I believe the answer is:

painfully

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'benefit completely will stop' is the definition.
I can't tell whether this defines the answer.

'distressing fashion' is the wordplay.
'distressing' becomes 'painful' (similar in meaning).
'fashion' becomes 'ly' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'painful'+'ly'='PAINFULLY'

'in' is the link.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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