Current airmen picked up after also crossing the boundary (5,3,3)

I believe the answer is:

going too far

'crossing the boundary' is the definition.
(as in going beyond a boundary)

'current airmen picked up after also' is the wordplay.
'current' becomes 'going' (I've seen this before).
'airmen' becomes 'raf'.
'picked up' is a reversal indicator.
'after' means one lot of letters go next to another.
'also' becomes 'too' (synonyms).
'raf' backwards is 'far'.
'far' put after 'too' is 'toofar'.
'going'+'toofar'='GOING TOO FAR'

I've seen this clue in The Guardian.

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