Announce end of labour for special postal service (7,8)

I believe the answer is:

express delivery

'special postal service' is the definition.
(faster delivery service)

'announce end of labour' is the wordplay.
'announce' becomes 'express' (both can mean to say out loud).
'end of labour' becomes 'delivery' (a baby is delivered after labour).
'express'+'delivery'='EXPRESS DELIVERY'

'for' acts as a link.

I've seen this clue in The Guardian.

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