Old Jack, seen as a rogue at Mile End (4)

I believe the answer is:

cade

I'm a little stuck... Click here to teach me more about this clue!

'old jack seen' is the definition.
I can't tell whether this definition defines the answer.

'a rogue at mile end' is the wordplay.
'a rogue' becomes 'cad' (I've seen this before).
'at' says to put letters next to each other.
'end' indicates one should take the final letters.
The last letter of 'mile' is 'e'.
'cad'+'e'='CADE'

'as' is the link.

Can you help me to learn more?

(Other definitions for cade that I've seen before include "Jack --, English rebel" , "Jack -, Kentish rebel" , "Rebel leader" , "Barrel" .)

I've seen this clue in the Evening Standard.

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