Thing amazingly preceding Californian autumn sunset (9)

I believe the answer is:

nightfall

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'sunset' is the definition.
(thesaurus)

'thing amazingly preceding californian autumn' is the wordplay.
'amazingly' indicates an anagram.
'preceding' means one lot of letters go next to another.
'californian autumn' becomes 'fall' (synonyms. I am not sure about the 'californian' bit.).
'thing' with letters rearranged gives 'night'.
'night'+'fall'='NIGHTFALL'

Can you help me to learn more?

(Other definitions for nightfall that I've seen before include "start of the dark time" , "Evening" , "after sunset" , "End of day" , "Dusk" .)

I've seen this clue in The Times.

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