Timely reminder (6)

I believe the answer is:

prompt

I believe this is a double definition.

'timely' is the first definition.
(synonyms)

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

(Other definitions for prompt that I've seen before include "Bring about; timely" , "On the dot" , "Urge - done without delay" , "Bang on" , "Precisely on time" .)

I've seen this clue in The Independent and The Telegraph.

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