Presumptuously claims spa town's demolishing hotel (9)

I believe the answer is:

arrogates

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'presumptuously claims' is the definition.
'arrogates' can be an answer for 'claims' ('arrogate' can be a synonym of 'claim'). I'm not sure about the 'presumptuously' bit.

'spa town's demolishing hotel' is the wordplay.
'spa town's' becomes 'Harrogate's'.
'demolishing' indicates named letters should be taken away.
'hotel' becomes 'h' (phonetic alphabet).
'harrogates' with 'h' taken out is 'ARROGATES'.

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I've seen this clue in The Independent.

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