If frost damaged everything to start with (5,2,3)

I believe the answer is:

first of all

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'to start with' is the definition.
I can't judge whether this definition defines the answer.

'if frost damaged everything' is the wordplay.
'damaged' is an anagram indicator.
'everything' becomes 'all' (all things).
'if'+'frost'='iffrost'
'iffrost' with letters rearranged gives 'firstof'.
'firstof'+'all'='FIRST OF ALL'

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(Other definitions for first of all that I've seen before include "Prime" , "Before anything else" , "initially" .)

I've seen this clue in the Evening Standard.

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