The most common and most likely answer to this crossword clue is the 8 letter word DEADLINE
I've seen this crossword clue in The Guardian
D
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A
D
L
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E
More clues leading to the result DEADLINE
- Ideal end, somehow, to meet this?
- Due date that's not welcomed by caller?
- Telephone fault, and when it should be fixed by?
- Insensitive column, a problem for the editor?
- Journalist often has this problem with broadband?
- Unmissable date — and phone not working?
- Closing time having passed, left drink unopened
- Closing date for journalist’s lifeless column
- State finally cutting parental counselling service? That’s the limit!
- Boring story about knight that shouldn’t be missed?
Buddy explains!

The straight part
We know that "Closing date/Closing date" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case closing date/closing date = deadline.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 DEADLINE mean?
DEADLINE noun- A time limit in the form of a date on or before which something must be completed.
- A guideline marked on a plate for a printing press.
- A line that does not move.
- A boundary around a prison, prisoners crossing which would be shot.
- To render an item non-mission-capable; to ground an aircraft, etc.