Old Tory plan upset singer (5,6)

I believe the answer is:

dolly parton

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'singer' is the definition.
I know nothing about this answer so I can't judge whether this works.

'old tory plan upset' is the wordplay.
'upset' is an anagram indicator.
'old'+'tory'+'plan'='oldtoryplan'
'oldtoryplan' is an anagram of 'DOLLY PARTON'.

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