Adding padding to English operas, following leading composer (12)

'adding' is the definition.
The definition and answer can be both to do with ownership as well as being present participle verbs.
Perhaps they are linked in a way I don't understand?

'padding to english operas following leading composer' is the wordplay.
I cannot really see how this works, but
'english' could be 'e' (abbreviation) and 'e' is located in the answer.
'leading' could be 'up' (up can mean leading in a game) and 'up' is found within the answer.
'composer' could be 'holst' (Gustav Holst) and 'holst' is present in the answer.
The remaining letters 'ring' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?