The most common and most likely answer to this crossword clue is the 5 letter word UNTIL
I've seen this crossword clue in The Daily Telegraph
U
N
T
I
L
More clues leading to the result UNTIL
- Jauntily up to appearing in that?
- To the point that peacekeepers fired back
- Before jaunt, I loaded cases
- Drunk Greek character returned before
- Up to taunt ill-natured guards
- Before deal, it nullified shepherds in turn
- Ruins trifle — odd ingredients should have been discarded before
- Before dark, light’s extremes revolved
- Prior to jaunt I laugh internally
- When bird’s taken off jauntily, what one gets up to
Buddy explains!

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.
What does UNTIL mean?
UNTIL preposition- Up to the time of (something happening).
- Up to (a certain place)
- Before (a time).
- To; physically towards.
- Up to the time that (a condition becomes true).
- Before (a condition becoming true).