When one gets it, tell thingummybob to spend year travelling (9,6)

I believe the answer is:

lightbulb moment

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'when one gets it' is the definition.
I can't judge whether this defines the answer.

'tell thingummybob to spend year travelling' is the wordplay.
'to spend' indicates named letters should be taken away (spend can mean to lose or waste).
'year' becomes 'y'.
'travelling' indicates an anagram.
'tell'+'thingummybob'='tellthingummybob'
'tellthingummybob' with 'y' removed is 'tellthingummbob'.
'tellthingummbob' with letters rearranged gives 'LIGHTBULB MOMENT'.

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I've seen this clue in The Telegraph.

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