Kestrel let her fly free but in a haphazard way (6,7)

I believe the answer is:

helter skelter

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'free but in a haphazard way' is the definition.
I can't tell whether this definition defines the answer.

'kestrel let her fly' is the wordplay.
'fly' indicates anagramming the letters.
'kestrel'+'let'+'her'='kestrellether'
'kestrellether' anagrammed gives 'HELTER-SKELTER'.

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(Other definitions for helter skelter that I've seen before include "In disorder" , "in disorderly haste" , "recklessly" , "headlong" , "Slide" .)

I've seen this clue in The Daily Express.

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