Young Mr Pitt's publicity for British Rail (5)

I believe the answer is:

brads

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'young mr pitt's' is the definition.
I can't judge whether this defines the answer.

'publicity for british rail' is the wordplay.
'publicity' becomes 'ads' (advert).
'for' means one lot of letters go next to another (I've seen this in other clues).
'british rail' becomes 'br'.
'ads' put after 'br' is 'BRADS'.

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I've seen this clue in the Evening Standard.

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