Liberal gets terribly old - time to leave (6)

I believe the answer is:

letsgo

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'time to leave' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'liberal gets terribly old' is the wordplay.
'liberal' becomes 'l' (abbreviation).
'terribly' indicates anagramming the letters.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'gets' is an anagram of 'etsg'.
'l'+'etsg'+'o'='LETSGO'

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I've seen this clue in The Daily Express.

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