Please note bird that’s passed (4)
I believe the answer is:
dodo
'bird that's passed' is the definition.
(extinct bird)
'please note' is the wordplay.
'please' becomes 'do' (I've seen this in other clues).
'note' becomes 'do' (musical note, as in do-re-mi).
'do'+'do'='DODO'
(Other definitions for dodo that I've seen before include "Two rooks - one was unable to fly" , "Ultra-conservative" , "silly person" , "E [EXTINCT] bird" , "Old fogey" .)