Puts back about a record which is an increase (4-2)

I believe the answer is:

step-up

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

'puts back about a record' is the wordplay.
'back' says the letters should be written backwards.
'about' indicates putting letters inside.
'a record' becomes 'EP' (abbreviation for extended play record).
'puts' written backwards gives 'stup'.
'stup' enclosing 'ep' is 'STEP-UP'.

'which' acts as a link.

(Another definition for step-up that I've seen is " Accelerate - promotion".)

I've seen this clue in the Sydney Morning Herald.

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