The most common and most likely answer to this crossword clue is the 8 plus 4 letter word ELEVENTH HOUR
I've seen this crossword clue in The Daily Telegraph
E
L
E
V
E
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H
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O
U
R
More clues leading to the result ELEVENTH HOUR
- Last moment in episode with leaders in historic hostilities, once in control, retreating
- Last minute volunteer, he, first to hurry off
- The last moment, when conflict ended?
- Last minute gives time for refreshments
- Vide Matthew 20:6 or 23:59
- Latest possible moment for silently remembering the Armistice?
- English frown about smooth Brexit finally getting doubly hard in last possible moment
Buddy explains!

The straight part
We know that "Last minute" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case last minute = eleventh hour.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.