Heading for Newport having left English city suddenly (6)

I believe the answer is:

presto

'suddenly' is the definition.

I cannot understand how the remainder of the clue works.

(Other definitions for presto that I've seen before include "hey......,cries the magician" , "Hey ..., according to the magician" , "Hey ..., said the magician" , "(In music) fast" , "In a quick tempo (music)" .)

I've seen this clue in The Times.

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