Mission one: punctual BBC debate (8,4)

I believe the answer is:

question time

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'bbc debate' is the definition.
I can't tell whether this definition defines the answer.

'mission one punctual' is the wordplay.
'mission' becomes 'quest' (a quest is a mission or search).
'one' becomes 'i' (Roman numeral).
'punctual' becomes 'on time' (being on time is being punctual).
'quest'+'i'+'ontime'='QUESTION TIME'

Can you help me to learn more?

(Another definition for question time that I've seen is " Parliamentary occasion".)

I've seen this clue in The Guardian.

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