What superstar expects ringing about one after lead? (3,7)

I believe the answer is:

top billing

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'what superstar expects ringing' is the definition.
I can't tell whether this definition defines the answer.

'one after lead?' is the wordplay.
'one' becomes 'billing' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'after' is a charade indicator (letters next to each other).
'lead?' becomes 'top' (I've seen this in other clues).
'billing' after 'top' is 'TOP BILLING'.

'about' is the link.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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