GP innovates flying flag (6,5)

I believe the answer is:

paving stone

'flag' is the definition.
(flagstone)

'gp innovates flying' is the wordplay.
'flying' is an anagram indicator (letters fly around into new positions).
'gp'+'innovates'='gpinnovates'
'gpinnovates' is an anagram of 'PAVING STONE'.

(Another definition for paving stone that I've seen is " Slab".)

I've seen this clue in The Guardian.

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