Note to change flag (6)

I believe the answer is:

falter

'flag' is the definition.
(I've seen this before)

'note to change' is the wordplay.
'note' becomes 'f' (musical note).
'to change' becomes 'alter' (altering is a kind of changing).
'f'+'alter'='FALTER'

(Other definitions for falter that I've seen before include "Lose momentum" , "flag" , "Hesitate, waver" , "Hesitate, be uncertain" , "Hesitate, vacillate" .)

I've seen this clue in The Globe and Mail and The Guardian.

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