Most upset with hotel in Swiss resort (2,6)

I believe the answer is:

st moritz

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'swiss resort' is the definition.
The definition suggests a singular noun which matches the answer.

'most upset with hotel' is the wordplay.
'upset' indicates an anagram.
'with' is a charade indicator (letters next to each other).
'hotel' becomes 'ritz' (I've seen this before).
'most' is an anagram of 'stmo'.
'stmo'+'ritz'='ST MORITZ'

'in' acts as a link.

Can you help me to learn more?

I've seen this clue in The Independent.

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