Not quite happening (5,2)

I believe the answer is:

going on

I believe this is a double definition.

'not quite' is the first definition.
(eg going on 13 - nearly 13 years old)

'happening' is the second definition.
('go on' can be a synonym of 'happen')

(Other definitions for going on that I've seen before include "Almost" , "reluctant to stop?" , "Continuing" .)

I've seen this clue in The Guardian.

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