An upset abstainer very stern and stylish (5)

I believe the answer is:

natty

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'stylish' is the definition.
(I've seen this before)

'an upset abstainer very stern' is the wordplay.
'upset' says the letters should be written backwards.
'abstainer' becomes 'tt' (I've seen this in other clues).
'very stern' becomes 'y' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'an' back-to-front is 'na'.
'na'+'tt'+'y'='NATTY'

'and' is the link.

Can you help me to learn more?

(Other definitions for natty that I've seen before include "Stylish" , "Flashily smart" , "Smart, fashionable (colloq.)" , "Dapper (colloq.)" , "Smart, spruce" .)

I've seen this clue in The Daily Express.

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