Engineers note combine getting crop up again (2-6)

I believe the answer is:

re-emerge

'crop up again' is the definition.
(emerge or appear again)

'engineers note combine getting' is the wordplay.
'engineers' becomes 're' (abbreviation for Royal Engineers).
'note' becomes 'e' (musical note).
'combine' becomes 'merge' (synonyms).
'getting' means one lot of letters go next to another.
're'+'e'+'merge'='RE-EMERGE'

(Another definition for re-emerge that I've seen is " Come out again".)

I've seen this clue in The Times.

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