No raid or surprise bit of advancement (6)

I believe the answer is:

inroad

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'no raid' is the definition.
'inroad' can be an answer for 'raid' (I've seen this before). I'm not sure about the 'no' bit.

I don't understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for inroad that I've seen before include "Foray" , "One's intrusive" , "Incursion, raid" , "Offensive" , "Encroachment, intrusion" .)

I've seen this clue in The Hindu.

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